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1.
Appl Radiat Isot ; 181: 110073, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34971924

RESUMO

Safe, effective, cost-effective, easy feasible and low-waste decontamination technologies are fundamental importance from environmental and radiation protection aspects. In this study the effectiveness of AP-CITROX decontamination technology of Inconel alloy 690 was investigated. Non-radioactive representative metal samples were formed to test of decontamination technology and the clear-, the corroded-, the decontaminated layer were analysed electrochemically. The results indicate that the passivation step of the technology was not completed.


Assuntos
Ligas , Cromo , Descontaminação/métodos , Níquel , Humanos , Análise Espectral
2.
Phys Rev Lett ; 127(23): 232002, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34936768

RESUMO

We discuss spontaneously broken quantum field theories with a continuous global symmetry group via the constraint effective potential. Employing lattice simulations with constrained values of the order parameter, we demonstrate explicitly that the path integral is dominated by inhomogeneous field configurations and that these are unambiguously related to the flatness of the effective potential in the broken phase. We determine characteristic features of these inhomogeneities, including their topology and the scaling of the associated excess energy with their size. Concerning the latter we introduce the differential surface tension-the generalization of the concept of a surface tension pertaining to discrete symmetries. Within our approach, spontaneous symmetry breaking is captured merely via the existence of inhomogeneities, i.e., without the inclusion of an explicit breaking parameter and a careful double limiting procedure to define the order parameter. While here we consider the three-dimensional O(2) model, we also elaborate on possible implications of our findings for the chiral limit of QCD.

3.
Appl Radiat Isot ; 170: 109594, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33476942

RESUMO

Although chloride compounds are the main cause of corrosion damage in distillation unit, standard methods to determine them do not guarantee good results. In this study, the chloride concentration of different crude oils was measured using different techniques and the results were compared. ASTM D3230, D4929 as standard methods, XRF as alternative technique and Neutron Activation Analysis as reference method, were applied. It is concluded that XRF method is an effective technique for measuring the chloride concentration of oils.

4.
J Environ Radioact ; 229-230: 106543, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33515923

RESUMO

Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Ração Animal/análise , Animais , Radioisótopos de Césio/análise , Galinhas , Poluentes Radioativos do Solo/análise
5.
J Environ Radioact ; 228: 106510, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341753

RESUMO

Thoron (220Rn) exhalation from building materials has become increasingly recognized as a potential source for radiation exposure in dwellings. However, contrary to radon (222Rn), limited information on thoron exposure is available. As a result no harmonized test procedures for determining thoron exhalation from building materials are available at present. This study is a first interlaboratory comparison of different test methods to determine the thoron exhalation and a pre-step to a harmonized standard. The purpose of this study is to compare the experimental findings from a set of three building materials that are tested, and to identify future challenges in the development of a harmonized standard.


Assuntos
Poluentes Radioativos do Ar , Materiais de Construção , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Expiração , Habitação , Radônio/análise
6.
Dig Dis Sci ; 66(10): 3495-3504, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33128681

RESUMO

BACKGROUND: Dieulafoy's lesion (DL) is a rare but increasingly recognized cause of severe upper GI hemorrhage (SUGIH). There is little consensus regarding the endoscopic approach to management of bleeding from DL. AIMS: Our purposes were to compare 30-day outcomes of patients with SUGIH from DL with Doppler endoscopic probe (DEP) monitoring of blood flow and guided treatment versus standard visually guided hemostasis (VG). METHODS: Eighty-two consecutive DL patients with SUGIH were identified in a large CURE Hemostasis database from previous prospective cohort studies and two recent RCTs at two university-based medical centers. 30-day outcomes including rebleeding, surgery, angiography, death, and severe medical complications were compared between the two treatment groups. RESULTS: 40.2% of DL bleeds occurred in inpatients. 43.9% of patients had cardiovascular disease, and 48.7% were taking medications associated with bleeding. For the entire cohort, 41.3% (26/63) of patients treated with VG had a composite 30-day outcome as compared to 10.5% (2/19) of patients treated with DEP (p = 0.017). Rebleeding occurred within 30 days in 33.3% and 10.5% of those treated with VG and DEP, respectively (p = 0.051). After propensity score matching, the adjusted 30-day composite outcome occurred in 39.0% in the VG group compared to 2.6% in the DEP group (p < 0.001). Adjusted 30-day rebleeding occurred in 25.3% in the VG group versus 2.6% in the DEP group (p < 0.001). DISCUSSION: DL patients with SUGIH were frequently inpatients and had severe cardiovascular comorbidities and recurrent bleeding. Lesion arterial blood flow monitoring and obliteration are an effective way to treat bleeding from DL which reduces negative 30-day clinical outcomes.


Assuntos
Pressão Arterial , Artérias/anormalidades , Hemorragia Gastrointestinal/etiologia , Trato Gastrointestinal/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia do Sistema Digestório , Feminino , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Resultado do Tratamento , Adulto Jovem
7.
J R Soc Interface ; 17(173): 20200648, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33292097

RESUMO

Standard epidemic models based on compartmental differential equations are investigated under continuous parameter change as external forcing. We show that seasonal modulation of the contact parameter superimposed upon a monotonic decay needs a different description from that of the standard chaotic dynamics. The concept of snapshot attractors and their natural distribution has been adopted from the field of the latest climate change research. This shows the importance of the finite-time chaotic effect and ensemble interpretation while investigating the spread of a disease. By defining statistical measures over the ensemble, we can interpret the internal variability of the epidemic as the onset of complex dynamics-even for those values of contact parameters where originally regular behaviour is expected. We argue that anomalous outbreaks of the infectious class cannot die out until transient chaos is presented in the system. Nevertheless, this fact becomes apparent by using an ensemble approach rather than a single trajectory representation. These findings are applicable generally in explicitly time-dependent epidemic systems regardless of parameter values and time scales.


Assuntos
Doenças Transmissíveis , Epidemias , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Humanos , Dinâmica não Linear
8.
Phys Rev E ; 102(4-1): 042202, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33212712

RESUMO

We study the connection between transport phenomenon and escape rate statistics in two-dimensional standard map. For the purpose of having an open phase space, we let the momentum coordinate vary freely and restrict only angle with periodic boundary condition. We also define a pair of artificial holes placed symmetrically along the momentum axis where the particles might leave the system. As a consequence of the leaks the diffusion can be analyzed making use of only the ensemble of survived particles. We present how the diffusion coefficient depends on the size and position of the escape regions. Since the accelerator modes and, thus, the diffusion are strongly related to the system's control parameter, we also investigate effects of the perturbation strength. Numerical simulations show that the short-time escape statistics do not follow the well-known exponential decay especially for large values of perturbation parameters. The analysis of the escape direction also supports this picture as a significant amount of particles skip the leaks and leave the system just after a longtime excursion in the remote zones of the phase space.

9.
Physiol Int ; 107(2): 349-358, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32692716

RESUMO

Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.

10.
PLoS One ; 15(7): e0235109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609724

RESUMO

Data on the transfer of artificial radionuclides from the environment to the food supply is necessary for internal dose assessment. There is a necessity for expanding and improving the available information on these factors in order to make better dose models for specific scenarios. This paper describes the results of a field experiment with broiler chickens on the transfer factor (Ff) and concentration ratio (CR) for the long-term intake of 241Am and 137Cs with grass meal and soil. The broilers were divided into two groups, each group had nine subgroups and each subgroup had three broilers. The radionuclide concentrations in the feed and the thigh muscle, thigh bone, and liver of 54 broilers divided between the grass meal and soil groups were evaluated by gamma spectrometry for 241Am and 137Cs. The duration of feeding with "contaminated" sources ranged between 1-70 days. The equilibrium stage of 241Am in muscle and bone occurs on the 1st and 40th day, respectively; for 137Cs in muscle- 30th days of intake and for liver and bone- 7th days. For 241Am, the liver did not reach equilibrium stage during the 70 days of intake. Ff of 137Cs in the "forage-muscle" and "soil-muscle" systems were determined as 1.9±0.3 and 0.18±0.05; Ff of 241Am in the "soil-muscle" system was-7.5×10-5.


Assuntos
Amerício/análise , Radioisótopos de Césio/análise , Galinhas , Contaminação Radioativa de Alimentos/análise , Aves Domésticas , Poluentes Radioativos do Solo/análise , Amerício/metabolismo , Ração Animal/análise , Animais , Radioisótopos de Césio/metabolismo , Galinhas/metabolismo , Abastecimento de Alimentos , Aves Domésticas/metabolismo , Poluentes Radioativos do Solo/metabolismo
11.
J Environ Radioact ; 222: 106322, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32565415

RESUMO

Horses are important food sources in several countries however, data on their radionuclide uptake is less available than for many other farm animals. Information on the transfer of artificial radioisotopes from the environment to the food supply is necessary for internal dose assessment and assuring the safety of the population relying on this food source. This study provides data for a less studied farm animal and, in the case of 241Am and 239+240Pu, relatively poorly studied radionuclides with respect to transfer to animal products. The transfer parameters for 239+240Pu, 241Am, 137Cs and 90Sr to the organs of 1-year old fillies, 10-year old mares and through the placental barrier into foetuses were quantified after 60-days feeding with contaminated soil or diet contaminated by a leachate solution. The transfer of radionuclides from ingested soil to tissues was generally lower, by up to three orders of magnitude, than from a diet contaminated by a leachate solution. The ingestion of soil is a particularly important source of radionuclide intake to grazing animals in the Semipalatinsk Test Site. For 241Am there is a lack of available data, the two singular entries for mutton and beef in the IAEA handbook are higher than all values observed in the current study. The maximum observed transfer factor for 241Am was 72 ± 22*10-5 d kg-1 FW in the liver of the mare fed with leachate contaminated feed. For 239+240Pu the maximum transfer factor was 31.8 ± 8*10-5 d kg-1 FW observed also in the liver of the mare fed with leachate contaminated feed. The filly fed with leachate contaminated feed had the highest transfer parameter value for 137Cs, 35.3*10-3 d kg-1 FW. The highest 90Sr transfer factor was found in the ribs of the filly fed leachate contaminated feed, 720 ± 144 *10-3 d kg-1 FW. The results presented in this paper can be used to improve the current internal dose estimates from the ingestion of horse meat produced in the area, however they are based on a low sample size; future studies need to use a larger number of animals.


Assuntos
Radioisótopos de Césio , Cavalos , Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Estrôncio , Animais , Bovinos , Radioisótopos de Césio/farmacocinética , Feminino , Gravidez , Poluentes Radioativos do Solo/farmacocinética , Radioisótopos de Estrôncio/farmacocinética
13.
Eur J Surg Oncol ; 46(4 Pt A): 522-526, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31740186

RESUMO

INTRODUCTION: Determining the extent of residual disease in the breast and axilla following neoadjuvant chemotherapy (NACT) is vital for surgical planning. Traditionally patients with incomplete radiological response in the breast after NACT undergo axillary node clearance, regardless of axillary clinical and radiological response. The aim of this study was to determine whether radiological and/or pathological response in the breast to NACT were predictive of axillary response. MATERIALS AND METHODS: A retrospective cohort study of patients with operable breast cancer with histologically proven axillary lymph node involvement who received NACT and underwent definitive surgical treatment between 1/1/2016 and 31/12/2018 were included. All had MRI and/or US of the breast and axilla before, mid-treatment and at the end of NACT. RESULTS: The 83 patients had a median age of 50 years (range 25-77). MRI had a positive predictive value (PPV) of 52.6% and negative predictive value (NPV) of 81.8% for breast pathological complete response (pCR). For axillary pCR, US had a PPV of 60.0% and NPV of 89.6%. Only 71% of patients had radiological concordance; 15.9% had radiological complete response (rCR) in breast and axilla whilst 55.1% had neither breast nor axillary rCR. 85.6% of patients had pathological concordance (20.5% with breast and axillary pCR: 65.1% with residual disease in both). CONCLUSION: Radiological and pathological response in the breast to NACT does not accurately predict axillary response. The axilla and the breast should be viewed and assessed as two separate entities for treatment plans.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linfonodos/diagnóstico por imagem , Adulto , Idoso , Axila , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Valor Preditivo dos Testes , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Resultado do Tratamento , Ultrassonografia
15.
Radiat Prot Dosimetry ; 184(3-4): 338-341, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31329995

RESUMO

Monthly precipitation samples have been collected at Toki, Japan, from November 2013 to March 2017. In this report, selected data were analysed to identify the regional hydrogen and oxygen isotope compositions. Tritium (3H) concentration in the precipitation ranged from 0.10 to 0.61 Bq L-1 and higher 3H concentrations were observed in spring rather than in other seasons. This range was similar to values reported in Chiba City, Japan. 3H concentration and the ratio d-excess, and δD values were roughly clustered according to each separate season. These regional hydrogen and oxygen isotope compositions will be used for environmental assessments of effects of the deuterium plasma experiments of the large fusion test device.


Assuntos
Hidrogênio/análise , Isótopos de Oxigênio/análise , Monitoramento de Radiação/métodos , Contagem de Cintilação/instrumentação , Trítio/análise , Poluentes Radioativos da Água/análise
16.
J Environ Radioact ; 208-209: 105988, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31176957

RESUMO

We evaluated the applicability of neutron activation analysis for investigating the potential mobility of 90Sr in a pasture area in Hungary. To measure strontium concentrations, we made use of the 84Sr(n,γ)85Sr radiative capture reaction using neutron activation analysis and performed gamma spectroscopy using Compton-suppression techniques on the resulting 514.0 keV gamma ray. Our values for soil-to-plant transfer factors value of 1.6 (2.2) kg kg-1 were in agreement with recommended values from the ICRP and IAEA, as well as similar studies performed by independent researchers. Our values for plant-to-animal transfer coefficients and concentration ratios varied from suggested values by several orders of magnitude to agreement with other values. Based on our results the utilized transfer of stable strontium could not be regarded as a convenient substitute to help clarify the long-term transfer of radioactive strontium in the environment, because short term dosing was applied. Neutron activation analysis provides a unique niche as a technique with very little chemical processing and short sample analysis times.


Assuntos
Cadeia Alimentar , Análise de Ativação de Nêutrons , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Radioisótopos de Estrôncio/análise , Hungria , Plantas
17.
Eur J Surg Oncol ; 45(9): 1515-1519, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31085024

RESUMO

As part of its mission to promote the best surgical care for cancer patients, the European Society of Surgical Oncology (ESSO) has been developing multiple programmes for clinical research along with its educational portfolio. This position paper describes the different research activities of the Society over the past decade and an action plan for the upcoming five years to lead innovative and high quality surgical oncology research. ESSO proposes to consider pragmatic research methodologies as a complement to randomised clinical trials (RCT), advocates for increased funding and operational support in conducting research and aims to enable young surgeons to be active in research and establish partnerships for translational research activities.


Assuntos
Pesquisa Biomédica/tendências , Ensaios Clínicos como Assunto , Assistência à Saúde Culturalmente Competente , Projetos de Pesquisa/tendências , Oncologia Cirúrgica/tendências , Europa (Continente) , Humanos , Sociedades Médicas
18.
Radiat Prot Dosimetry ; 184(3-4): 474-478, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31135915

RESUMO

The outdoor radon concentration was monitored together with the meteorological parameters at two contrasting complex topographies: sub-Alpine basin (SA) and sub-Mediterranean valley (SM) in winter (December 2017-February 2018) and summer (June-August 2018). The time series for each site and each season are evaluated in three different ways: (i) clear-sky and cloudy condition together, (ii) clear-sky conditions only (cloud cover <20%) and (iii) cloudy condition only (cloud cover >20%), and compared to the expected atmospheric boundary layer (ABL) 'mixing volume' caused by meteorological changes. The results have confirmed the sensitivity of diurnal and seasonal radon concentration to the expected ABL 'mixing volume' at the two selected sites. The relationship is more pronounced in calm clear-sky conditions. Cloudy conditions are associated with fast weather changes, when the ABL is well mixed and hourly mean radon concentrations do not follow the typical diurnal trend.


Assuntos
Poluentes Radioativos do Ar/análise , Sedimentos Geológicos/análise , Meteorologia , Monitoramento de Radiação/métodos , Radônio/análise , Estações do Ano , Poluentes Radioativos da Água/análise , Tempo (Meteorologia)
20.
Biomed Res Int ; 2019: 2971741, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719441

RESUMO

Campylobacter jejuni is one of the most common food-borne bacteria that causes gastrointestinal symptoms. In the present study we have investigated the molecular basis of the anti-Campylobacter effect of peppermint essential oil (PEO), one of the oldest EO used to treat gastrointestinal diseases. Transcriptomic, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and proteomic, two-dimensional polyacryl amid gel electrophoresis (2D-PAGE) methods have revealed that, in the presence of a sublethal concentration of PEO, the expression of several virulence-associated genes was decreased (cheY 0.84x; flhB 0.79x; flgE 0.205x; cadF 0.08x; wlaB 0.89x; porA 0.25x; cbf2 4.3x) while impaired motility was revealed with a functional analysis. Scanning electron micrographs of the exposed cells showed that, unlike in the presence of other stresses, the originally curved C. jejuni cells straightened upon PEO exposure. Gaining insight into the molecular background of this stress response, we have revealed that in the presence of PEO C. jejuni dominantly exerts a general stress response that elevates the expression of general stress genes like dnaK, groEL, groES (10.41x, 3.63x, and 4.77x). The most important genes dps, sodB, and katA involved in oxidative stress responses showed however moderate transcriptional elevations (1,58x, 1,55x, and 1,85x).


Assuntos
Campylobacter jejuni/efeitos dos fármacos , Mentha piperita/química , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/farmacologia , Virulência/efeitos dos fármacos , Proteínas de Bactérias/genética , Perfilação da Expressão Gênica/métodos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteômica/métodos , Transcrição Gênica/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
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