1,721,091 research outputs found
Concentration of 210Po in vegan diet foods commercialized in Italy and dose calculation
Full text linkIngestion of food and drink is one of the main routes by which radioactive elements in the environment enter the human body, which is why it is essential to know the concentration of the most significant naturally occurring and anthropogenic radionuclides in the diet. The radionuclide that is the subject of this work is 210Po, a radionuclide whose radiotoxicity is comparable to that of 239Pu and is about five times greater than that of 226Ra. To date, natural and artificial radioactivity has been measured in various foodstuffs in Italy. However, there needs to be more sufficient data concerning the vegan diet. This particular diet excludes all foods of animal origin, which is becoming increasingly popular. According to Eurispes' Italy 2021 Report, it has been estimated that 2,4 % of the Italian population follows a vegan diet. The first objective of this work was to complete previous alpha spectrometry measurement campaigns of 210Po carried out by the same research group on typical foods of the vegan diet (legumes, cereals, and their derivatives, pseudocereals, algae, and spices) to contribute to more comprehensive databases. The second objective was calculating the committed effective dose resulting from one year of food consumption, using the concentration data obtained in the analyzed samples. The concentration values obtained ranged from a minimum of 0,069 ± 0,051 Bq kg−1 in cereal and legume products to a maximum of 3,89 ± 2,79 Bq kg−1 in algae. The committed effective dose for the average adult related to the consumption of these foods was 67,7 μSv y−1
Neptunium-237 determination in depleted uranium ammunition by alpha spectrometry
No full textIt is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the DU origin (natural uranium enrichment of or spent nuclear fuel reprocessing) it is necessary to check the presence of activation products (236U, 239Pu, 240Pu, 241Am and 237Np, etc.) in the ammunition. Uranium isotopes, 239Pu, 240Pu, 241Am concentrations in DU were determined in the past in our Laboratory: the present paper describes a new and accurate method for the separation and determination of 237Np ultratraces in a DU penetrator.
After sample dissolution, neptunium was separated by two chromatographic columns consisting of micropourous polyethylene (Icorene) supporting tri-n-octylamine (TNOA); after elettrodeposition, Np was counted by alpha spectrometry.
The decontamination factor of neptunium from uranium was higher than 106; the detection limit was 0.5 Bq/kg for 0.10 g of ammunition; the average Np yield was 54.0 ± 3.1%. 237Np concentration in DU resulted 30.1 ± 2.4 Bq/kg.
The presence of this anthropogenic radionuclides in the penetrator indicates once more that at least part of the uranium originated from the reprocessing of nuclear fuel, but, because of the very low concentration, its radiotoxicological effect is negligible
Determination of essential and non essential elements in some medicinal plants by polarised X rays fluorescence spectrometer (EDPXRF)
No full textIn this study the elemental composition of some medicinal plants used in Italy by
polarised X rays fluorescence spectrometer (EDPXRF) was evaluated. EDPXRF is a
simultaneous, reliable, sensitive, quantitative multielemental and non-destructive
technique, suitable for routine analysis due to minimal sample preparation. This
technique has been used successfully by various authors for the characterization of
different complex matrices. The elements taken into account are 23 subdivided in
essential (macro and micro) and nonessential or toxic. Among the essential elements
estimated in the present work we found the micro and trace elements (Mn, Fe, Co, Cu,
Zn, Ni, Cr, Cl, Br, I) and macro elements (K, Mg, Ca, P, S); along the nonessential
elements and the toxic elements Al, Rb, Sr, As, Cd, Sn, Pb and Hg are taken into
account. Although the direct linkage between elemental concentration in plants and
their reported curative potentials is yet to be established, information on the levels of
inorganic elements in plants is important in understanding the pharmacological and
toxicological actions of medicinal plants in general.The results obtained in the analysis
of some medicinal plants showed the presence of essential elements that could
enhance the curative process of ill health, as well as the presence of potentially toxic
elements
RADIOLOGICAL CHARACTERIZATION OF PHOSPHATE FERTILIZERS: COMPARISON BETWEEN ALPHA AND GAMMA SPECTROMETRY
No full textThe natural radioactivity, 238U, 234U, 235U, 228Th, 230Th , 232Th 210Pb , 210Po 226Ra , 228Ra and40K, has
been measured in phosphate fertilizers used in central Italy. Radiological characterization of
phosphate fertilizers was performed by alpha and gamma spectrometry and the comparison between
the results obtained by these two techniques was done.
The concentration activities for the different radionuclides found in the fertilizer samples are
different; it can be due to the different concentration of uranium and thorium series radionuclides in
the raw material (phosphatic rock) and to the different composition of fertilizers. In the samples
analyzed it is possible to observe that the 234U/238U activity ratio is approximately one. While the
226Ra/234U and 210Po/234U activity ratios are clearly lower than one indicating that the majority of
210Po and 226Ra tends to remain in the phosphogypsum. While the U-isotopes tend to be in solution
with phosphoric acid from which all fertilizers derive. A very good correlation exists between the
activity concentrations found by alpha spectrometry and those found by gamma spectrometry .
Continued application of phosphate fertilizers to soil over a period of many years could eventually
increase the radium and uranium content of the soil, which would result in an increase of the dose to
bone. In any case in order to estimate the environmental impact of fertilizers use, it is necessary to
evaluate the transfer of radionuclides and their concentration distribution in the environmental
matrices such as soil,vegetation, milk, etc. and the individual doses by using mathematical models
Intake of 210Po, 234U and 238U radionuclides with wine in Italy
No full textWine is a widely consumed beverage in the world. Natural radioactivity has been
measured in drinking and mineral water and soft but there are not data for wine. For
this beverage, data are reported only on the artificial radioactivity (particularly 137Cs)
after Chernobyl. The composition of wine is influenced by many factors related to the
specific production as area, grape varieties, soil and climate and viticultural practices.
There are several sources contributing to wine contamination, and it is known that
radionuclides occur in wine from fruit contamination which can result from direct
deposition on fruit surfaces, absorption by the fruit skin and transport to the pulp,
deposition to soil, root uptake and transfer to fruit . This study provides some
information on the levels of natural radionuclides 238U, 234U isotopes and 210Po in
samples of red and white wine product in the different Italian regions. The committed
effective dose from 210Po, 234U and 238U for the individual local public through wine
ingestion was calculated. The results show that, for most of the samples, the 210Po
concentration is ten times higher than that of 238U. This fact is probably due to fallout of
atmospheric polonium on the leaves of the vines and on the grape.The data also
indicate that, in wine, the uranium concentration is lower that in water, whereas, the
polonium concentration is higher that in water
STAT5 and STAT5 Inhibitors in Hematological Malignancies
No full textThe JAK-STAT pathway is an important physiologic regulator of different cellular functions including proliferation, apoptosis, differentiation, and immunological responses. Out of six different STAT proteins, STAT5 plays its main role in hematopoiesis and constitutive STAT5 activation seems to be a key event in the pathogenesis of several hematological malignancies. This has led many researchers to develop compounds capable of inhibiting STAT5 activation or interfering with its functions. Several anti-STAT5 molecules have shown potent STAT5 inhibitory activity in vitro. However, compared to the large amount of clinical studies with JAK inhibitors that are currently widely used in the clinics to treat myeloproliferative disorders, the clinical trials with STAT5 inhibitors are very limited. At present, a few STAT5 inhibitors are in phase I or II clinical trials for the treatment of leukemias and graft vs host disease. These studies seem to indicate that such compounds could be well tolerated and useful in reducing the occurrence of resistance to tyrosine kinase inhibitors in chronic myeloid leukemia. Of interest, STAT5 seems to play an important role in the regulation of hematopoietic stem cell self-renewal suggesting that combination therapies including STAT5 inhibitors can erode the cancer stem cell pool and possibly open the way for the complete cancer eradication. In this review, we discuss the implication of STAT5 in hematological malignancies and the results obtained with the novel STAT5 inhibitors
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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