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1.
Appl Radiat Isot ; 210: 111364, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38843648

RESUMEN

166Ho (T1/2≈ 26.8 h) is an emerging theragnostic radionuclide of interest in nuclear medicine due to its peculiar decay scheme, featuring high-energy ß- emission (≈ 1.8 MeV) coupled with the main gamma-ray emission (≈ 80.6 keV). Using the new 166Ho activity standard and the well-calibrated, high-energy resolution HPGe detector, both available at ENEA-INMRI, a new determination of several 166Ho gamma-ray emission intensities, Iγ, was performed with low uncertainty. The new Iγ values contributed to the Decay Data Evaluation Project.

2.
Diagn Microbiol Infect Dis ; 107(2): 116028, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37499605

RESUMEN

The aim of this work was associate the presence of the virulence factors of Helicobacter pylori, cagA/cagE, with gastric illness. We found evidence that indicate the contribution of these genotypes with the severity of gastric lesions in patients infected, principally in histological subtypes as atrophic gastritis, and metaplasia.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Mucosa Gástrica , Genotipo , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/genética
3.
Eur Rev Med Pharmacol Sci ; 26(1 Suppl): 84-91, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36448860

RESUMEN

OBJECTIVE: The use of megaprosthetic implants could provide substantial advantages in elderly population affected by complex fractures. The aim of the study was to identify the patients suitable to megaprosthetic implants in the treatment of lower limbs fractures, as well as periprosthetic fractures. PATIENTS AND METHODS: From January 1st, 2015, to December 31st, 2021, all patients affected by femoral fractures with severe bone loss or previous surgery failure were retrospectively reviewed. ADL, IADL, SF-12 values pre- and post-operative were recorded. Hemoglobin value, NLR, PLR were recorded pre- and peri-operatively for all patients. Complications were recorded. All patients underwent a radiological follow-up. Significance was set at p ≤ 0.05. RESULTS: 23 patients were considered eligible, 10 males and 13 females; the mean age was 72.87 years old (± 12.33), while the mean BMI was 27.2 points (± 5.2). The mean follow-up was 2 years (± 1.4). The mean preoperative ADL and IADL scores were correlated with a positive independence of the patient, while the mean postoperative scores corresponded to a moderate-low independence. Also the mean Mental and Physical SF12 scores saw a decrease in values. NLR values were higher in the first group of patients with complications. CONCLUSIONS: A careful multiparametric and multidisciplinary patient selection is required to identify the suitable patient to this treatment.


Asunto(s)
Fracturas del Fémur , Extremidad Inferior , Femenino , Masculino , Humanos , Anciano , Estudios Retrospectivos , Extremidad Inferior/cirugía , Algoritmos , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/cirugía , Periodo Posoperatorio
4.
Eur Rev Med Pharmacol Sci ; 26(1 Suppl): 9-15, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36448864

RESUMEN

OBJECTIVE: Proximal femur fractures are among the most common type of trauma in elderly patients, and Euthyroid sick syndrome has already been related to fractures and trauma. The evidence of a consistent inflammatory state occurring during hip fracture, made us consider as a potential marker also the neutrophil-to-lymphocyte ratio (NLR), which is already in use to measure the prognosis and guide the therapeutic management in various conditions. PATIENTS AND METHODS: A retrospective observational analysis on patients affected by proximal femur fractures was conducted. Patients were divided between affected and non-affected by Euthyroid Sick Syndrome (ESS). Standard follow up was conducted at 1, 3, 6 and 12 months. RESULTS: 79 patients were enrolled in this study. There were 19 males and 60 females, the mean age was 83.8 ± 6.5 y.o., and 44 patients were affected by ESS. Affected patients showed higher NLR values (10.2 ± 9.4 vs. 6.9 ± 3.9; p= 0.001) and higher decrease in fT3 values in the 1st post-operative day (1.8 ± 0.4 vs. 2.2 ± 0.3; p= 0.001), higher values of PTH (97.9 ± 46.2 vs. 70.1 ± 36.2; p=0.004) and lower levels of Vitamin D (18.8 ± 7.8 vs. 23.5 ± 12.9; p= 0.04). As regards complications, we found them in 27% of patients in group A, while only in 8% in Group B, with a statistically significant difference (p= 0.03). CONCLUSIONS: ESS and NLR are promising prognostic markers in PFF in the elderly patients. If used together, they could help in the pre- and post-operative management of the patients.


Asunto(s)
Síndromes del Eutiroideo Enfermo , Fracturas del Fémur , Anciano , Femenino , Masculino , Humanos , Anciano de 80 o más Años , Neutrófilos , Síndromes del Eutiroideo Enfermo/diagnóstico , Estudios Retrospectivos , Linfocitos , Fémur
5.
Ann Oncol ; 32(6): 787-800, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33746047

RESUMEN

BACKGROUND: Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies. PATIENTS AND METHODS: Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients). RESULTS: A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality. CONCLUSIONS: Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies. CLINICAL TRIAL IDENTIFIER: NCT04354701.


Asunto(s)
COVID-19 , Neoplasias , Anciano , Prueba de COVID-19 , Femenino , Humanos , Masculino , Neoplasias/tratamiento farmacológico , Neoplasias/epidemiología , Pandemias , SARS-CoV-2
6.
Appl Radiat Isot ; 144: 34-46, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30522082

RESUMEN

The emission probabilities of γ rays produced in the 227Ac decay series were determined by high-resolution γ-ray spectrometry of sources with standardised activity. The sources were prepared quantitatively on glass discs by drop deposition of a solution with 227Ac in radioactive equilibrium with its daughter nuclides. Their activity was measured by a primary standardisation technique based on alpha-particle counting at a defined low solid angle. Four laboratories performed γ-ray spectrometry and derived absolute γ-ray intensities. Mean values were calculated and compared with literature data and the currently recommended evaluated data. New values on certain γ-ray emission probabilities are proposed.

7.
Appl Radiat Isot ; 134: 105-107, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29066213

RESUMEN

A severe supply crisis of 99Mo, precursor of 99mTc a diagnostic radionuclide largely used in Nuclear Medicine, occurred in 2008-2009 due to repeated shut-down of the two main (aged) fission reactors. An alternative route for producing 99Mo by 100Mo(n,2n)99Mo reaction was investigated at ENEA. The experiment, designed according to Monte Carlo simulations performed with the Fluka code, produced 99Mo by irradiating a natural Molybdenum powdered target with 14MeV neutrons produced at the Frascati Neutron Generator. The 99Mo specific activity was measured at metrological level by γ-ray spectrometry.

8.
Appl Radiat Isot ; 134: 380-384, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29032880

RESUMEN

A bilateral comparison between ENEA-INMRI (Italy) and NCBJ RC POLATOM (Poland) of 131I-solution activity measurements was organized in the year 2015 and piloted by POLATOM, which provided the sources for the comparison. The 131I master solution was standardized independently at both institutes by using Liquid Scintillation Counting and ionization chamber techniques. The 131I master solution was then sent by POLATOM to the BIPM International Reference System (SIR). The comparison was registered as an EURAMET.RI(II)-K2.I-131 key comparison allowing the ENEA-INMRI result to enter in the SIR database.

9.
Transl Oncol ; 10(3): 346-356, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28342318

RESUMEN

OBJECTIVE: The ROR1 and ROR2 receptor tyrosine kinases have both been implicated in ovarian cancer progression and have been shown to drive migration and invasion. There is an increasing importance of the role of stroma in ovarian cancer metastasis; however, neither ROR1 nor ROR2 expression in tumor or stromal cells has been analyzed in the same clinical cohort. AIM: To determine ROR1 and ROR2 expression in ovarian cancer and surrounding microenvironment and examine associations with clinicopathological characteristics. METHODS: Immunohistochemistry for ROR1 and ROR2 was used to assess receptor expression in a cohort of epithelial ovarian cancer patients (n=178). Results were analyzed in relation to clinical and histopathological characteristics and survival. Matched patient sample case studies of normal, primary, and metastatic lesions were used to examine ROR expression in relation to ovarian cancer progression. RESULTS: ROR1 and ROR2 are abnormally expressed in malignant ovarian epithelium and stroma. Higher ROR2 tumor expression was found in early-stage, low-grade endometrioid carcinomas. ROR2 stromal expression was highest in the serous subtype. In matched patient case studies, metastatic samples had higher expression of ROR2 in the stroma, and a recurrent sample had the highest expression of ROR2 in both tumor and stroma. CONCLUSION: ROR1 and ROR2 are expressed in tumor-associated stroma in all histological subtypes of ovarian cancer and hold potential as therapeutic targets which may disrupt tumor and stroma interactions.

10.
Appl Radiat Isot ; 126: 138-145, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28187932

RESUMEN

Characterization and calibration measurements were carried out at the National Institute of Ionizing Radiation Metrology of ENEA on the TAp WAter RAdioactivity (TAWARA) Real Time Monitor system recently developed for real time monitoring of radioactive contamination in water processed at water treatment facilities. Reference radiations and radionuclides were chosen in order to reflect energy ranges and radiation types of the major water radioactive contaminants possibly arising from environmental, industrial or terroristic origin. The following instrument parameters were tested: sensitivity, selectivity, background, short/long term stability, linearity with respect to activity.


Asunto(s)
Sistemas de Computación , Monitoreo de Radiación/instrumentación , Contaminantes Radiactivos del Agua/análisis , Purificación del Agua , Partículas alfa , Partículas beta , Calibración , Sistemas de Computación/estadística & datos numéricos , Diseño de Equipo , Humanos , Monitoreo de Radiación/normas , Monitoreo de Radiación/estadística & datos numéricos , Radioisótopos/análisis , Estándares de Referencia , Espectrometría gamma , Contaminantes Radiactivos del Agua/normas , Contaminación Radiactiva del Agua/análisis , Purificación del Agua/normas
11.
Eur Phys J C Part Fields ; 77(7): 471, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30828260

RESUMEN

We give an introduction to several regularization schemes that deal with ultraviolet and infrared singularities appearing in higher-order computations in quantum field theories. Comparing the computation of simple quantities in the various schemes, we point out similarities and differences between them.

12.
Phys Med ; 32(12): 1745-1752, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27692753

RESUMEN

Peptide receptor therapy with 177Lu-labelled somatostatin analogues is a promising tool in the management of patients with inoperable or metastasized neuroendocrine tumours. The aim of this work was to perform accurate activity quantification of 177Lu in complex anthropomorphic geometry using advanced correction algorithms. Acquisitions were performed on the higher 177Lu photopeak (208keV) using a Philips IRIX gamma camera provided with medium-energy collimators. System calibration was performed using a 16mL Jaszczak sphere surrounded by non-radioactive water. Attenuation correction was performed using µ-maps derived from CT data, while scatter and septal penetration corrections were performed using the transmission-dependent convolution-subtraction method. SPECT acquisitions were finally corrected for dead time and partial volume effects. Image analysis was performed using the commercial QSPECT software. The quantitative SPECT approach was validated on an anthropomorphic phantom provided with a home-made insert simulating a hepatic lesion. Quantitative accuracy was studied using three tumour-to-background activity concentration ratios (6:1, 9:1, 14:1). For all acquisitions, the recovered total activity was within 12% of the calibrated activity both in the background region and in the tumour. Using a 6:1 tumour-to-background ratio the recovered total activity was within 2% in the tumour and within 5% in the background. Partial volume effects, if not properly accounted for, can lead to significant activity underestimations in clinical conditions. In conclusion, accurate activity quantification of 177Lu can be obtained if activity measurements are performed with equipment traceable to primary standards, advanced correction algorithms are used and acquisitions are performed at the 208keV photopeak using medium-energy collimators.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Lutecio , Radioisótopos , Tomografía Computarizada de Emisión de Fotón Único , Humanos , Fantasmas de Imagen , Relación Señal-Ruido , Técnica de Sustracción
13.
Appl Radiat Isot ; 112: 156-64, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27064195

RESUMEN

Over the last years (177)Lu has received considerable attention from the clinical nuclear medicine community thanks to its wide range of applications in molecular radiotherapy, especially in peptide-receptor radionuclide therapy (PRRT). In addition to short-range beta particles, (177)Lu emits low energy gamma radiation of 113keV and 208keV that allows gamma camera quantitative imaging. Despite quantitative cancer imaging in molecular radiotherapy having been proven to be a key instrument for the assessment of therapeutic response, at present no general clinically accepted quantitative imaging protocol exists and absolute quantification studies are usually based on individual initiatives. The aim of this work was to develop and evaluate an approach to gamma camera calibration for absolute quantification in tomographic imaging with (177)Lu. We assessed the gamma camera calibration factors for a Philips IRIX and Philips AXIS gamma camera system using various reference geometries, both in air and in water. Images were corrected for the major effects that contribute to image degradation, i.e. attenuation, scatter and dead- time. We validated our method in non-reference geometry using an anthropomorphic torso phantom provided with the liver cavity uniformly filled with (177)LuCl3. Our results showed that calibration factors depend on the particular reference condition. In general, acquisitions performed with the IRIX gamma camera provided good results at 208keV, with agreement within 5% for all geometries. The use of a Jaszczak 16mL hollow sphere in water provided calibration factors capable of recovering the activity in anthropomorphic geometry within 1% for the 208keV peak, for both gamma cameras. The point source provided the poorest results, most likely because scatter and attenuation correction are not incorporated in the calibration factor. However, for both gamma cameras all geometries provided calibration factors capable of recovering the activity in anthropomorphic geometry within about 10% (range -11.6% to +7.3%) for acquisitions at the 208keV photopeak. As a general rule, scatter and attenuation play a much larger role at 113keV compared to 208keV and are likely to hinder an accurate absolute quantification. Acquisitions of only the (177)Lu main photopeak (208keV) are therefore recommended in clinical practice. Preliminary results suggest that the gamma camera calibration factor can be assessed with a standard uncertainty below (or of the order of) 3% if activity is determined with equipment traceable to primary standards, accurate volume measurements are made, and an appropriate chemical carrier is used to allow a homogeneous and stable solution to be used during the measurements.


Asunto(s)
Cámaras gamma , Lutecio , Radioisótopos , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Calibración , Cámaras gamma/estadística & datos numéricos , Humanos , Interpretación de Imagen Asistida por Computador , Fantasmas de Imagen , Tomografía Computarizada de Emisión de Fotón Único/normas , Tomografía Computarizada de Emisión de Fotón Único/estadística & datos numéricos
14.
Phys Lett B ; 761: 281-286, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-28057978

RESUMEN

The hypothesis that proximity to the Sun causes variation of decay constants at permille level has been tested and disproved. Repeated activity measurements of mono-radionuclide sources were performed over periods from 200 days up to four decades at 14 laboratories across the globe. Residuals from the exponential nuclear decay curves were inspected for annual oscillations. Systematic deviations from a purely exponential decay curve differ from one data set to another and are attributable to instabilities in the instrumentation and measurement conditions. The most stable activity measurements of alpha, beta-minus, electron capture, and beta-plus decaying sources set an upper limit of 0.0006% to 0.008% to the amplitude of annual oscillations in the decay rate. Oscillations in phase with Earth's orbital distance to the Sun could not be observed within a 10-6 to 10-5 range of precision. There are also no apparent modulations over periods of weeks or months. Consequently, there is no indication of a natural impediment against sub-permille accuracy in half-life determinations, renormalisation of activity to a distant reference date, application of nuclear dating for archaeology, geo- and cosmochronology, nor in establishing the SI unit becquerel and seeking international equivalence of activity standards.

15.
Appl Radiat Isot ; 109: 17-23, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26682894

RESUMEN

In 2014, the first three comparisons of activity measurements of (18)F were carried out at the VNIIM, NPL and the ENEA-INMRI using the BIPM's Transfer Instrument of the International Reference System. The transfer instrument and the NMIs primary measurement methods are briefly described. The degrees of equivalence with the key comparison reference value defined in the frame of the corresponding SIR comparison have been evaluated. World-wide consistency of activity measurements of (18)F is demonstrated.


Asunto(s)
Radioisótopos de Flúor/análisis , Radioisótopos de Flúor/normas , Laboratorios/normas , Medicina Nuclear/normas , Radiometría/normas , Internacionalidad , Dosis de Radiación , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Homo ; 65(4): 311-21, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24767538

RESUMEN

Recent forensic studies have shown that the hyoid bone is a sexually dimorphic element of the human skeleton. Given the advanced techniques of collecting human remains in archeological and forensic contexts, the recovery of hyoid bones is now more frequent in skeletal samples. For that reason the authors propose a new method for estimating sex based on hyoid bodies from archeological sites. The study has been conducted on well-preserved hyoids of skeletal remains of 64 adult individuals (44 males and 20 females) dated from the pre-Roman to the medieval periods. The authors considered 10 linear measurements of the hyoid body. The most significant measurements showing sexual dimorphism are the body height, body length, and the maximum and minimum diameter of the articular facet for the greater horn. Discriminant function analysis achieved the allocation accuracy between 75.0% and 88.0%, depending on the measurement collected. This method represents a new, useful and easy way for increasing biological information when assessing the sex of adult human remains from an archeological sample.


Asunto(s)
Fósiles/anatomía & histología , Hueso Hioides/anatomía & histología , Determinación del Sexo por el Esqueleto/métodos , Adulto , Arqueología , Femenino , Historia del Siglo XV , Historia Antigua , Historia Medieval , Humanos , Italia , Masculino , Persona de Mediana Edad , Ciudad de Roma , Caracteres Sexuales , Adulto Joven
17.
J Diabetes Res ; 2013: 486593, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24171177

RESUMEN

OBJECTIVES: of this study were to assess diastolic function in pregnant women with abnormal glucose tolerance (AGT), compared with normal glucose tolerance (NGT) women, and to evaluate the insulin resistance status and its association with Doppler-echocardiographic indexes. Echocardiograms of 108 consecutive Caucasian women with singleton pregnancies were performed. Insulin resistance status was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI). All the studied women showed normal diastolic patterns. Patients with AGT (50.9%), as compared with NGT women, had higher HOMA-IR (1.70 ± 1.30 versus 1.01 ± 0.81, P = 0.003), lower QUICKI (0.36 ± 0.005 versus 0.40 ± 0.06, P = 0.004), higher lateral mitral annulus late diastolic velocity (13.6 ± 4.9 versus 11.9 ± 4.9, P = 0.03), and higher A-wave velocity, the wave responsible for the active atrial contraction component (75.2 ± 14.2 versus 67.7 ± 16.2, P = 0.01). At multivariate regression analysis HOMA-IR was the only parameter associated with A-wave velocity. In conclusion, women with AGT had an increased subclinical diastolic active participation, which is associated with higher levels of insulin resistance. For the increased risk of deterioration of cardiac diastolic function, earlier and more seriously than normal pregnancy, AGT women may have a careful followup to detect the early signs of cardiac alteration and to prevent cardiovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/prevención & control , Diástole , Intolerancia a la Glucosa/complicaciones , Intolerancia a la Glucosa/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Diagnóstico Prenatal/métodos , Adulto , Enfermedades Asintomáticas , Estudios de Casos y Controles , Diagnóstico Precoz , Ecocardiografía Doppler , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/prevención & control , Adulto Joven
19.
Appl Radiat Isot ; 70(9): 2075-80, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22464789

RESUMEN

A (177)Lu primary standard was developed at the ENEA-INMRI in the frame of an international comparison organized by BIPM and piloted by NIST (USA). The CIEMAT/NIST method with (3)H standard source as tracer was used for standardizing a solution of (177)Lu. The activity value was compared also with the measurements of the same mother solution carried out by the 4πγ integral counting method. Particular efforts were made to identify and quantify the long-lived (177m)Lu impurity in the mother solution. The results obtained by the two methods are in good agreement within their standard uncertainties. The arithmetic mean of the two values is in good agreement with the Comparison Reference Value (CRV). By the new primary standard two well-type ionization chambers (ICs), one fixed and the other one portable, were calibrated with an uncertainty lower than 2%. These ICs are used for routinely applications in the activity measurements of short-lived radionuclides particularly useful for medical applications.


Asunto(s)
Lutecio/análisis , Lutecio/normas , Radioisótopos/análisis , Radioisótopos/normas , Radiometría/normas , Semivida , Internacionalidad , Dosis de Radiación , Estándares de Referencia , Valores de Referencia
20.
Appl Radiat Isot ; 70(9): 2119-23, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22476014

RESUMEN

The effect of radon diffusion and distribution between a (226)Ra matrix and the top air gap inside sample containers for gamma-ray spectrometry was studied. Containers filled at almost 100% or just 70% of total capacity yielded correction factors of about 7% and 20% respectively. Applying these correction factors allowed activity values calculated from (226)Ra or radon decay products to agree within 2%.


Asunto(s)
Algoritmos , Artefactos , Radiometría/normas , Radón/análisis , Radón/normas , Espectrometría gamma/métodos , Espectrometría gamma/normas , Aire , Semivida , Internacionalidad , Transición de Fase , Dosis de Radiación , Radiometría/métodos , Radón/química , Estándares de Referencia , Valores de Referencia , Soluciones
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