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Chlorella vulgaris is of great importance in numerous exploratory or industrial applications (e.g., medicals, food, and feed additives). Rapid quantification of algal biomass is crucial in photobioreactors for the optimization of nutrient management and the estimation of production. The main goal of this study is to provide a simple, rapid, and not-resource-intensive estimation method for determining the algal density of C. vulgaris according to the measured parameters using UV-Vis spectrophotometry. Comparative assessment measurements were conducted with seven different methods (e.g., filtration, evaporation, chlorophyll a extraction, and detection of optical density and fluorescence) to determine algal biomass. By analyzing the entire spectra of diluted algae samples, optimal wavelengths were determined through a stepwise series of linear regression analyses by a novel correlation scanning method, facilitating accurate parameter estimation. Nonlinear formulas for spectrometry-based estimation processes were derived for each parameter. As a result, a general formula for biomass concentration estimation was developed, with recommendations for suitable measuring devices based on algae concentration levels. New values for magnesium content and the average single-cell weight of C. vulgaris were established, in addition to the development of a rapid, semiautomated cell counting method, improving efficiency and accuracy in algae quantification for cultivation and biotechnology applications.
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Cowden syndrome (CS) is a rare genetic condition due to the various germline mutations in the phosphatase and tensin homologue on chromosome ten (PTEN) tumour suppressor gene. As a result, CS is characterised by an increased risk of developing various benign and malignant tumours, such as thyroid, breast, endometrial and urogenital neoplasms, as well as gastrointestinal tract tumours. However, the neuroendocrine tumour association with CS is not elucidated yet. We present a case of a 46-year-old male patient diagnosed with testicular seminoma and follicular thyroid cancer in his medical history. Our patient met the clinical diagnostic criteria of Cowden syndrome. Genetic analysis established the clinical diagnosis; a known heterozygous PTEN mutation was detected [PTEN (LRG_311t1)c.388 C > T (p.Arg130Ter)]. Incidentally, he was also seen with multiple pulmonary lesions during his oncological follow-up. A video-assisted thoracoscopic left lingula wedge resection and later resections from the right lung were performed. Histological findings revealed typical pulmonary carcinoid tumours and smaller tumorlets. Somatostatin receptor SPECT-CT, 18F-FDG-PET-CT and 18F-FDOPA-PET-CT scans and endoscopy procedures could not identify any primary tumours in other locations. Our patient is the first published case of Cowden syndrome, associated with multifocal pulmonary carcinoids. Besides multiple endocrine neoplasia type 1, we propose Cowden syndrome as another hereditary condition predisposing to multiple pulmonary tumorlets and carcinoid tumours.
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Tumor Carcinoide , Síndrome de Hamartoma Múltiple , Humanos , Síndrome de Hamartoma Múltiple/genética , Síndrome de Hamartoma Múltiple/complicaciones , Síndrome de Hamartoma Múltiple/patología , Síndrome de Hamartoma Múltiple/diagnóstico , Persona de Mediana Edad , Masculino , Tumor Carcinoide/complicaciones , Tumor Carcinoide/genética , Tumor Carcinoide/patología , Tumor Carcinoide/diagnóstico , Neoplasias de los Bronquios/genética , Neoplasias de los Bronquios/diagnóstico por imagen , Neoplasias de los Bronquios/complicaciones , Neoplasias de los Bronquios/patología , Neoplasias de los Bronquios/diagnóstico , Fosfohidrolasa PTEN/genéticaRESUMEN
BACKGROUND: Breast cancer is the leading cancer in women globally. Despite decreasing mortality rates, largely due to early detection and modern treatment, the effectiveness of screening on long-term survival outcomes remains unclear. AIMS: This study evaluates the 15-year survival outcomes of a national breast cancer screening program initiated in Hungary in 2002. METHODS: Using a prospectively maintained patient database, the study included individuals from the first 6 years of the program who underwent surgery for histologically confirmed breast cancer and had available follow-up information. Patients were categorized based on the method of breast cancer detection into two groups: those diagnosed during or 2 years after the population-based screening exam (Group A), and those who self-detected or sought medical attention for symptoms (Group B). RESULTS: Of the 309 patients who underwent breast cancer surgery, 208 were screen-detected (Group A) and 101 were symptomatic (Group B). The 15-year overall survival was 75.0% for Group A and 76.2% for Group B (p = 0.927). The 15-year disease-specific survival was 85.6% and 81.2% (p = 0.249), respectively. A statistically not significant positive trend in disease-free survival was observed in Group A (81.7% vs. 75.2%; p = 0.144). CONCLUSIONS: The study underscores the importance of extended follow-up periods in evaluating the outcomes of breast cancer screening programs. While the screening program may not significantly enhance overall survival rates, it has demonstrated a reduction in the mastectomy rate and could potentially extend periods of disease-free survival. These findings contribute to the ongoing discourse about the long-term benefits of breast cancer screening programs.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Mamografía/métodos , Mastectomía , Tasa de Supervivencia , Hungría , Detección Precoz del Cáncer/métodos , Tamizaje Masivo/métodosRESUMEN
INTRODUCTION AND IMPORTANCE: Ganglioneuromas are extremely rare, slow-growing, benign tumors that arising from Schwann cells, ganglion cells, and neuronal or fibrous tissue. Their malignant degeneration occurs very rarely, complete surgical removal is recommended to eliminate possible symptoms or to prevent possible malignant transformation. Reviewing the literature, there is currently insufficient data available on laparoscopic resection of retroperitoneal ganglioneuromas. CASE PRESENTATION: 20-year-old young woman with no previous medical history or regular medication use complaints of abdominal pain. Abdominal CT scan found a cystic mass measuring up to 50 mm in diameter with a thick fluid density and no contrast accumulation, was identified in the porta hepatis region extrahepatically. Ultrasound-guided biopsy was performed, histopathological finding revealed mature benign neurogenic tumor tissue consisting of mature ganglion cells, mature Schwann cells, and branching stroma. CLINICAL DISCUSSION: A laparoscopic surgery was performed, the 5 cm large tumor was excised from the hepatoduodenal ligament. The tumor was removed from the region of the inferior caval vein, portal vein, and the common and proper hepatic arteries. Final histological diagnosis is ganglioneuroma of the hepatoduodenal ligament. After uneventful postoperative period, the patient was discharged home on the 6th day. CONCLUSIONS: Retroperitoneal tumors were previously excised during laparotomy. However, in recent decades, with the development of laparoscopic surgical techniques and tools, laparoscopic removal of some retroperitoneal tumors seems to be the ideal approach. The use of laparoscopy improves visibility of the relationship of the tumor to the surrounding, often vital, structures. Based on a review of the international literature and our own experience, laparoscopic ganglioneuroma resection is the recommended procedure with careful patient selection, as well as appropriate preoperative imaging and diagnostics, and with adequate expertise.
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Our 69-year-old female patient was investigated for a 20 kg weight gain over 2 years. The patient's medical history included hypertension, hyperuricemia, bilateral cataract surgery and musculosceletal complaints. Diabetes mellitus was not found. Physical examination revealed abdominal obesity, proximal myopathy and atrophic, vulnerable skin. The "overnight", low-dose and long, low-dose dexamethasone suppression tests indicated autonomous cortisol overproduction (plasma cortisol level: 172.6 and 153.2 nmol/L, cut-off: 50 nmol/L). The suppressed ACTH (<1.11 pmol/L, normal value: 1.12-10.75 pmol/L) suggested ACTH-independent hypercortisolism. Abdominal CT described macronodular enlargement of both adrenals. The size of the largest nodule was 23 × 20 mm in the right, and 24 × 30 mm on the left side (with -33 ± 37 HU density values on native scans). The 131I-cholesterol adrenal scintigraphy and SPECT/CT showed almost equally intensive radiopharmacon uptake on both sides. Based on the clinical results, bilateral macronodular adrenal hyperplasia associated with ACTH-independent hypercortisolism was diagnosed. Genomic DNA was obtained from the peripheral blood leukocytes. Targeted sequencing of 25 genes potentially involved in adrenal tumorigenesis revealed a new disease-causing armadillo repeat-containing 5 (ARMC5) gene mutation (c.1724del28 bp, g.31,476,067-31,476,094). Because of the autosomal dominant inheritance of this genetic alteration, the patient's two children underwent genetic screening for the ARMC5 mutation. The same mutation was found in the younger child of our patient. To the best of our knowledge, this is the first published Hungarian case of ARMC5 mutation with bilateral macronodular adrenal hyperplasia and ACTH-independent Cushing's syndrome. The genetic alteration is present in two generations of the family of the index patient. Orv Hetil. 2023; 164(32): 1271-1277.
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Hiperplasia Suprarrenal Congénita , Síndrome de Cushing , Femenino , Niño , Humanos , Anciano , Síndrome de Cushing/genética , Síndrome de Cushing/diagnóstico , Radioisótopos de Yodo , Hidrocortisona , Hiperplasia/genética , Proteínas Supresoras de Tumor/genética , Mutación , Hormona Adrenocorticotrópica/genética , Proteínas del Dominio Armadillo/genéticaRESUMEN
Introduction: 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. Materials and methods: 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. Results: 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%). Discussion: 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.
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Ganglio Linfático Centinela , Neoplasias Gástricas , Humanos , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Escisión del Ganglio Linfático/métodos , Ganglio Linfático Centinela/patología , Metástasis Linfática/patología , Estadificación de Neoplasias , Ganglios Linfáticos/patologíaRESUMEN
According to the World Health Organization, gastric cancer is the fifth most common type of tumor, and is the third most common cause of tumor-associated death. Although gastric cancer incidence rates have decreased in the past few decades, the prevalence of proximal gastric cancer has been steadily rising in developed countries. Techniques regarding the improvement of treatment options must thus be developed. This can be achieved through incorporating both a wider use of endoscopic surgery (endoscopic mucosal resection-EMR, endoscopic submucosal dissection-ESD) and a review of applied surgical interventions. Even though there is no single international consensus available, the Japanese Gastric Cancer Association (JGCA) recommends proximal gastrectomy with D1+ lymphadenectomy in early gastric tumors. Despite recommendations from Asian guidelines and the short term outcomes of the KLASS 05 trial, surgical treatments in Western countries still rely on total gastrectomy. This is mostly due to technical and oncological challenges regarding surgical interventions in a proximal gastrectomy. However, the residual stomach after a proximal gastrectomy has been shown to diminish the incidence of dumping syndrome and anemia, and even improve postoperative quality of life (QoL). Therefore, it is necessary to define the place of proximal gastrectomy in the treatment of gastric cancers.
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The successful production of maize is fundamentally determined by a good choice of tillage type. Options include conventional tillage based on soil rotation, as well as a more recent conservation approach. Our aims were to determine the stress physiological effects of the plant remains left behind by different tillage procedures on the juvenile maize plants, combined with the effects of fungicide treatment on the seeds. These effects were followed and investigated by means of biophoton emission measurement, an in vivo and non-invasive imaging technique, along with chlorophyll content estimation, as well as microbial- and polymerase chain reaction-based identification of fungi presence. Our results confirmed the response reactions of maize triggered by a soil covering plant remains on the initial development and physiological involvement of maize. The positive effects of seed treatment on initial development are manifested only at the final stage of the experiment. The fungal microbiological analysis confirmed the dominant presence of necrotrophic parasites on plant residues, the stress-inducing properties of which were possible to monitor by biophoton emission. Furthermore, the presence of Fusarium spp. was confirmed by PCR analysis from samples treated with plant residues.
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Growing of ornamental flowering plants represents an important sector of horticulture. Viola × wittrockiana (garden pansy) is used in garden beds and borders due to their colorful blooming, which occurs in early spring and late autumn. Nowadays, breeders focus on applying different nutrient solutions to improve the quality, flowering, and ornamental properties of plants, yet electrical conductivity (EC) level is an important fact to know. It is known that higher EC levels can inhibit plants' growth. In the present study, pansy seedlings were subjected to different EC nutrient solutions 1 (control), 2, 3.5, 5, and 6.5 mS cm-1 EC to assess the positive or negative effects regarding the plant's growth and development. The results indicated that an appropriate EC level of nutrient solution can have a positive effect on growth parameters, as well as on the flowering of plants. According to the hierarchical clustering, the used EC nutrient solutions significantly influenced the growth, number of shoots and leaves and the inflorescences number. From the present study results, it can be concluded that even though all EC levels increased growth parameters compared with control, the greatest results were obtained in plants under the effect of the 5 mS cm-1 of EC.
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Gastric cancer still remains a major cause of cancer-related deaths globally. Stage-adapted, individualized treatment is crucial to achieving optimal oncological outcomes. Postoperative morbidity and accurate nodal staging are heavily influenced by the extent of lymph node dissection. On one hand, insufficient lymphadenectomy may result in understaging and undertreatment of a patient, on the other hand, unnecessary lymph node dissection may result in a higher rate of postoperative complications. Approximately one-third of patients with gastric cancer undergoes an avoidable lymph node dissection. Many of the recent treatment updates in the management of gastric cancer have a major influence on both surgical and oncological approaches. Currently, a wide range of endoscopic, minimally invasive, and hybrid surgical techniques are available. The concept of sentinel node biopsy and utilization of the Maruyama Computer Program are significant components of stage-adapted gastric cancer surgery. Likewise, centralization and application of national guidelines, widespread use of neoadjuvant therapy, and the stage migration phenomenon are serious concerns to be discussed. Our goal is to review the available surgical strategies for gastric cancer, with a primary focus on lymphadenectomy.
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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.
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Neoplasias Colorrectales , Pruebas Hematológicas/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/terapia , Supervivencia sin Enfermedad , Femenino , Humanos , Hungría , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Estudios ProspectivosRESUMEN
The current energy crisis and waste management problems have compelled people to find alternatives to conventional non-renewable fuels and utilize waste to recover energy. Pyrolysis of plastics, which make up a considerable portion of municipal and industrial waste, has emerged as a feasible resolution to both satisfy our energy needs and mitigate the issue of plastic waste. This study was therefore conducted to find a solution for plastic waste management problems, as well as to find an alternative to mitigate the current energy crisis. Pyrolysis of five of the most commonly used plastics, polyethylene terephthalate (PET), high- and low-density polyethylene (HDPE, LDPE), polypropylene (PP), and polystyrene (PS), was executed in a pyrolytic reactor designed utilizing a cylindrical shaped stainless steel container with pressure and temperature gauges and a condenser to cool down the hydrocarbons produced. The liquid products collected were highly flammable and their chemical properties revealed them as fuel alternatives. Among them, the highest yield of fuel conversion (82%) was observed for HDPE followed by PP, PS, LDPE, PS, and PET (61.8%, 58.0%, 50.0%, and 11.0%, respectively). The calorific values of the products, 46.2, 46.2, 45.9, 42.8 and 42.4 MJ/kg for LPDE, PP, HPDE, PS, and PET, respectively, were comparable to those of diesel and gasoline. Spectroscopic and chromatographic analysis proved the presence of alkanes and alkenes with carbon number ranges of C9-C15, C9-C24, C10-C21, C10-C28, and C9-C17 for PP, PET, HDPE, LDPE, and PS, respectively. If implemented, the study will prove to be beneficial and contribute to mitigating the major energy and environmental issues of developing countries, as well as enhance entrepreneurship opportunities by replicating the process at small-scale and industrial levels.
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Degraded and salt affected soils are appearing more often in cultivated areas. These specific problems could reduce nutrient uptake, which can result in quality and yield loss of the cultivated plants. In order to cope with this pedo-climatic condition growers are applying fertilizers; however, due to inadequate application, soil degradation will continue. Five Gladiolus varieties were subjected to foliar fertilization treatments to assess the effect on the plant's growth parameters, vase durability and daughter corm production. Our results indicate that plants treated with foliar fertilization show significant increase in the measured parameters, flower stem length, vase durability and daughter corm production. In conclusion, our study suggests that application of foliar fertilization can increase Gladiolus plants decoration and propagation, even with a smaller footprint on nature.
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In view of safe management of the nuclear wastes, a sound knowledge of the atomic-scale properties of U1-xMxO2+y nanoparticles is essential. In particular, their cation valences and oxygen stoichiometries are of great interest as these properties drive their diffusion and migration behaviors into the environment. Here, we present an in-depth study of U1-xCexO2+y, over the full compositional domain, by combining X-ray diffraction and high-energy resolution fluorescence detection X-ray absorption near-edge structure. We show, on one hand, the coexistence of UIV, UV, and UVI and, on the other hand, that the fluorite structure is maintained despite this charge distribution.
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Case report: Laparoscopic wedge resection of the subepithelial tumors of the stomach is a widely accepted and utilized approach. The use of this technique for lesions located near the gastroesophageal junction (GEJ) is rather limited by the high risk of consequential stenosis of the gastric inlet. The laparoscopic transgastric resection can be a feasible choice for this location. A 44-year-old male patient had been investigated for dysphagia, which confirmed a subepithelial gastric lesion. We performed the resection of the tumor using this technique. After the creation of pneumoperitoneum, the stomach was insufflated using an orogastric tube, then 3 balloon-type ports were inserted intragastrically. The 6×3×3 cm large tumor was resected and the mucosa was closed by running sutures. The specimen was placed into a plastic bag, then retrieved from the stomach and the abdominal cavity. The gastrotomy sites of the ports on the stomach were closed. A nasogastric tube was left in situ for 24-hours without any intraabdominal drains. The pneumoperitoneum time was 115 minutes long, blood loss or intraoperative complication was not noticed. The postoperative period was uneventful, and the patient was discharged from the hospital three days after surgery. The histological examination confirmed the diagnosis of leiomyoma. Summary: Even though the follow-up of the patient is ongoing, according to the scientific literature, transgastric resection of subepithelial tumors located near the GEJ is a safe and effective technique, which provides good functional results, without having a higher risk for recurrence.
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Laparoscopía , Recurrencia Local de Neoplasia , Adulto , Humanos , Masculino , Estómago , Resultado del TratamientoRESUMEN
Studies have focused on identifying combinations of insects and organic waste to optimise bio-conversion. Here, the effects of different diets (10% chicken feed complemented with 90% vegetable waste, garden waste, cattle manure, or horse manure) on growth and survival rates, and nutritional value of Zophobas morio and Tenebrio molitor larvae, and Acheta domesticus were investigated. Compared with chicken feed, organic waste decreased the individual larval weight, although green waste showed fewer negative effects than the manure. The macronutrient concentrations in garden waste were moderate compared with chicken feed, and vegetable waste was the poorest diet in terms of nutrient concentration, as revealed by the principal component analysis (PCA). There was no difference in weight between larvae reared on garden waste and those reared on vegetable waste. Tenebrio molitor and A. domesticus showed the maximum growth rates at 71-101 and 36-66 days of age at 22.5 ± 2.5 °C, respectively. The PCA showed that the protein and fibre concentrations were inversely proportional to fat concentration in the larvae. Acheta domesticus was rich in proteins, whereas Z. morio and T. molitor were rich in fat. Feeding nutrient-poor diets resulted in a lower protein and a higher fat concentration in the larvae.
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Global warming is not only affecting arid and semi-arid regions but also becoming a threat to agriculture in Central and Eastern European countries. The present study analyzes the responses to drought and salinity of two varieties of Lavandula angustifolia cultivated in Romania. Lavender seedlings were subjected to one month of salt stress (100, 200, and 300 mM NaCl) and water deficit (complete withholding of irrigation) treatments. To assess the effects of stress on the plants, several growth parameters and biochemical stress markers (photosynthetic pigments, mono and divalent ions, and different osmolytes) were determined in control and stressed plants after the treatments. Both stress conditions significantly inhibited the growth of the two varieties, but all plants survived the treatments, indicating a relative stress tolerance of the two varieties. The most relevant mechanisms of salt tolerance are based on the maintenance of foliar K+ levels and the accumulation of Ca2+ and proline as a functional osmolyte in parallel with increasing external salinities. Under water stress, significant increases of Na+ and K+ concentrations were detected in roots, indicating a possible role of these cations in osmotic adjustment, limiting root dehydration. No significant differences were found when comparing the stress tolerance and stress responses of the two selected lavender varieties.
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An intercomparison of the radio-chronometric ages of four distinct plutonium-certified reference materials varying in chemical form, isotopic composition, and period of production are presented. The cross-comparison of the different 234U/238Pu, 235U/239Pu, 236U/240Pu, and 241Am/241Pu model purification ages obtained at four independent analytical facilities covering a range of laboratory environments from bulk sample processing to clean facilities dedicated to nuclear forensic investigation of environmental samples enables a true assessment of the state-of-practice in "age dating capabilities" for nuclear materials. The analytical techniques evaluated used modern mass spectrometer instrumentation including thermal ionization mass spectrometers and inductively coupled plasma mass spectrometers for isotopic abundance measurements. Both multicollector and single collector instruments were utilized to generate the data presented here. Consensus values established in this study make it possible to use these isotopic standards as quality control standards for radio-chronometry applications. Results highlight the need for plutonium isotopic standards that are certified for 234U/238Pu, 235U/239Pu, 236U/240Pu, and 241Am/241Pu model purification ages as well as other multigenerational radio-chronometers such as 237Np/241Pu. Due to the capabilities of modern analytical instrumentation, analytical laboratories that focus on trace level analyses can obtain model ages with marginally larger uncertainties than laboratories that handle bulk samples. When isotope ratio measurement techniques like thermal ionization mass spectrometry and inductively coupled plasma mass spectrometry with comparable precision are utilized, model purification ages with similar uncertainties are obtained.
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Validated analytical measurement protocols for the fast and accurate determination of the uranium (U) isotopic composition (234U, 235U, 236U, 238U) of solid nuclear materials were developed employing ns-laser ablation (LA) coupled to multi-collector ICP-MS. The accuracy of the analytical procedure was assured by frequent (nâ¯=â¯65) analysis of a pressed pellet of certified isotopic reference material CRM U-030 (â¼3â¯wt% 235U). The expanded uncertainty (kâ¯=â¯2) for the n(235U)/n(238U) ratio was as low as 0.05%, rising to 0.62% and 1.09% for n(234U)/n(238U) and n(236U)/n(238U) ratios, respectively. LA-MC-ICP-MS measurements of a pressed pellet of certified isotopic reference material CRM U-020 (â¼2â¯wt% 235U) before analysis of each sample allowed calculation of the ion counter gains and mass bias correction. Both individual spot analysis and line scan analysis were used to measure n(234U)/n(238U), n(235U)/n(238U), and n(236U)/n(238U) ratios in two low-enriched UO2 pellets from the fourth Collaborative Materials Exercise (CMX-4), four seized low-enriched UO2 pellets intercepted from illicit trafficking and one metal sample consisting of depleted U. LA-MC-ICP-MS results of all investigated samples matched well with U isotope ratios obtained by thermal ionisation mass spectrometry (TIMS). This independent confirmation of the LA-MC-ICP-MS results by TIMS underpinned the high quality of generated analytical data. Acquisition of several thousand data points within a couple of minutes during line scan analysis yielded detailed information on the spatial distribution of the U isotopic composition of selected UO2 pellets, revealing straightforwardly their (in-)homogeneity on the µm-scale. Calculating skewness and half width of the frequency distributions of the n(235U)/n(238U) amount ratio allowed the quantitative assessment of the (in-)homogeneity of the investigated samples. This information allows drawing conclusions on the starting materials used for the production of the pellets. From a nuclear forensics perspective, LA-MC-ICP-MS provides quick, accurate results on the spatial distribution of major and minor U isotopes while preserving the sample i.e. piece of evidence, essentially intact.