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1.
Int J Biometeorol ; 66(6): 1067-1078, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35277746

RESUMO

Grape development and its quality are highly dependent on soil and weather conditions. Under the progressive warming, which can affect the suitability of typical varieties grown in a given area, the knowledge of the vine response to changes in climate is essential to stablish strategies to maintain the viticulture sector. This research presents an analysis of phenology and grape composition of the Carignan cultivar, during a 13-year period, at two locations in Rioja DOCa. Based on the results obtained and the projected changes in climate under climate change scenarios (RC4.5 and RCP8.5), the response of this cultivar was evaluated. Differences in the phenological dates of up to 18, 29 and 40 days, for flowering, veraison and harvest, respectively, were observed between the warmest and the coolest years. An advance of up to 5, 8 and 11 days, respectively, for the mentioned stages, is projected under the RCP4.5 scenario by 2050, which could be near 1.5*times higher under the RCP8.5 scenario. These advances will be mainly driven by the temperatures recorded in the previous period. Grape acidity was mainly driven by water availability, in particular during ripening, which imply a slight projected reduction due to precipitation changes but not significant effect due to increasing temperatures. The phenolic composition could be positively affected by increasing temperatures and increasing water deficits, since this variety does not always reach a complete maturity at present. Thus, under the projected warming scenarios, the suitability of Carignan in Rioja DOCa was confirmed.


Assuntos
Vitis , Mudança Climática , Espanha , Água , Tempo (Meteorologia)
2.
J Antimicrob Chemother ; 73(7): 1854-1861, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29635367

RESUMO

Objectives: Gonorrhoea and antimicrobial resistance (AMR) in Neisseria gonorrhoeae are major public health concerns globally. Enhanced AMR surveillance for gonococci is essential worldwide; however, recent quality-assured gonococcal AMR surveillance in Latin America, including Brazil, has been limited. Our aims were to (i) establish the first nationwide gonococcal AMR surveillance, quality assured according to WHO standards, in Brazil, and (ii) describe the antimicrobial susceptibility of clinical gonococcal isolates collected from 2015 to 2016 in all five main regions (seven sentinel sites) of Brazil. Methods: Gonococcal isolates from 550 men with urethral discharge were examined for susceptibility to ceftriaxone, cefixime, azithromycin, ciprofloxacin, benzylpenicillin and tetracycline using the agar dilution method, according to CLSI recommendations and quality assured according to WHO standards. Results: The levels of resistance (intermediate susceptibility) to tetracycline, ciprofloxacin, benzylpenicillin and azithromycin were 61.6% (34.2%), 55.6% (0.5%), 37.1% (60.4%) and 6.9% (8.9%), respectively. All isolates were susceptible to ceftriaxone and cefixime using the US CLSI breakpoints. However, according to the European EUCAST cefixime breakpoints, 0.2% (n = 1) of isolates were cefixime resistant and 6.9% (n = 38) of isolates had a cefixime MIC bordering on resistance. Conclusions: This study describes the first national surveillance of gonococcal AMR in Brazil, which was quality assured according to WHO standards. The high resistance to ciprofloxacin (which promptly informed a revision of the Brazilian sexually transmitted infection treatment guideline), emerging resistance to azithromycin and decreasing susceptibility to extended-spectrum cephalosporins necessitate continuous surveillance of gonococcal AMR and ideally treatment failures, and increased awareness when prescribing treatment in Brazil.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Gonorreia/epidemiologia , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/efeitos dos fármacos , Vigilância de Evento Sentinela , Adulto , Azitromicina/farmacologia , Brasil/epidemiologia , Ceftriaxona/farmacologia , Ciprofloxacina/farmacologia , Gonorreia/urina , Humanos , Masculino , Neisseria gonorrhoeae/isolamento & purificação , Adulto Jovem
3.
Biol Lett ; 13(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29212749

RESUMO

Hummingbirds feed from hundreds of flowers every day. The properties of these flowers provide these birds with a wealth of information about colour, space and time to guide how they forage. To understand how hummingbirds might use this information, researchers have adapted established laboratory paradigms for use in the field. In recent years, however, experimental inspiration has come less from other birds, and more from looking at other nectar-feeders, particularly honeybees and bumblebees, which have been models for foraging behaviour and cognition for over a century. In a world in which the cognitive abilities of bees regularly make the news, research on the influence of ecology and sensory systems on bee behaviour is leading to novel insights in hummingbird cognition. As methods designed to study insects in the laboratory are being applied to hummingbirds in the field, converging methods can help us identify and understand convergence in cognition, behaviour and ecology.


Assuntos
Aves/fisiologia , Cognição , Animais , Abelhas/fisiologia , Polinização
4.
Rev Gastroenterol Mex ; 82(2): 156-178, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28104319

RESUMO

INTRODUCTION: Probiotics are frequently prescribed in clinical practice. Their efficacy in treating gastrointestinal disorders is supported by a significant number of clinical trials. However, the correct prescription of these agents is hampered due to a lack of knowledge of the scientific evidence and to the different presentations and microbial compositions of the probiotics that are currently available. AIM: To provide the clinician with a consensus review of probiotics and recommendations for their use in gastroenterology. MATERIALS AND METHODS: Controlled clinical trials, meta-analyses, and systematic reviews published up to 2015 were selected, using the MESH terms: probiotics, gastrointestinal diseases, humans, adults, AND children. The Delphi method was employed. Eighteen gastroenterologists treating adult patients and 14 pediatric gastroenterologists formulated statements that were voted on until agreement>70% was reached. The level of evidence based on the GRADE system was evaluated for each statement. RESULTS AND CONCLUSIONS: Eleven statements on the general concepts of probiotics and 27 statements on the use of probiotics in gastrointestinal diseases in both adults and children were formulated. The consensus group recommends the use of probiotics under the following clinical conditions: the prevention of diarrhea associated with antibiotics, the treatment of acute infectious diarrhea, the prevention of Clostridium difficile infection and necrotizing enterocolitis, the reduction of adverse events from Helicobacter pylori eradication therapy, relief from irritable bowel syndrome symptoms, the treatment of functional constipation in the adult, and the induction and maintenance of remission in patients with ulcerative colitis and pouchitis, and the treatment of covert and overt hepatic encephalopathy.


Assuntos
Gastroenterologia , Probióticos/uso terapêutico , Adulto , Criança , Consenso , Técnica Delphi , Guias como Assunto , Humanos , México
5.
Int J Biometeorol ; 59(12): 1849-60, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25906047

RESUMO

The aim of this work was to analyze spatial phenology and grape quality variability related to the climatic characteristics within the Ribera del Duero Designation of Origin (DO). Twenty plots planted with cv. Tempranillo and distributed within the DO were analyzed for phenology from 2004 to 2013. Grape quality parameters at ripening (berry weight, sugar content, acidity and pH, and anthocyanins) were analyzed in 26 plots for the period 2003-2013. The relationships between phenology and grape parameters with different climatic variables were confirmed with a multivariate analysis. On average, bud break was April 27(th), bloom June 17(th), and veraison August 12th. However, phenology during the time period showed high variability, with differences between years of up to 21 days for a phenology stage. The earliest dates were observed in dry years (2005, 2006, and to a lesser degree in 2009) while the later phenology dates occurred in the wettest year of the period (2008). High correlations were found between veraison date and temperature variables as well as with precipitation-evapotranspiration recorded during the bloom-veraison period. These effects tended to be higher in the central part of the DO. Grape quality parameters also showed high variability among the dry and the wet years, and the influence of extreme temperatures on color development as well as the effect of available water on acidity were observed.


Assuntos
Clima , Vitis/crescimento & desenvolvimento , Estações do Ano , Espanha , Temperatura
6.
J Appl Microbiol ; 117(3): 800-11, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24917056

RESUMO

AIMS: As reliability of preharvest applications of biological control agents (BCAs) to control fruit pathogens is highly dependent on the survival of the selected organism, this study aimed to describe the population dynamics of the yeast-BCA Candida sake (Saito & Ota) CPA-1 on grape berries under the effect of abiotic factors such as temperature, relative humidity, sunlight and rainfall. METHODS AND RESULTS: Candida sake (5 × 10(7) CFU ml(-1)), combined with different concentrations of the food additive Fungicover(®), was applied on grape berry clusters. Treated clusters were then exposed to abiotic factors in field or laboratory conditions, recovering populations to describe C. sake population dynamics. The addition of Fungicover significantly increased C. sake multiplication under optimal growth conditions and improved survival under fluctuating abiotic factors. After field applications, significant differences in populations on grape bunches exposed or covered by fine foliage were detected. Simulated rainfall washed off C. sake populations by 0·6-0·9 log units after 20 mm of rain volume. Allowing populations to establish for 24 h or more, prior to a rain event, persistence on grape berries significantly increased and the effect of rain intensity was not observable. CONCLUSIONS: Candida sake demonstrated high survival ability under unfavourable environmental conditions and persistence under intense rain. The study evidenced the importance of the first period just after application for C. sake survival on grape tissues and also the protective effect of the additive Fungicover. SIGNIFICANCE AND IMPACT OF THE STUDY: This research provides new information on the survival of C. sake under field conditions and its practical implications for recommending timing of spray with this antagonist. Our results could be useful for other yeast antagonists applied before harvest. This work, for the first time, defines population dynamics of a yeast BCA using simulated rainfall.


Assuntos
Agentes de Controle Biológico , Candida/fisiologia , Vitis/microbiologia , Aditivos Alimentares , Frutas/microbiologia , Viabilidade Microbiana , Chuva
7.
Phys Med ; 117: 103199, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38142615

RESUMO

Hadron therapy is a radiotherapy modality which offers a precise energy deposition to the tumors and a dose reduction to healthy tissue as compared to conventional methods. However, methods for real-time monitoring are required to ensure that the radiation dose is deposited on the target. The IRIS group of IFIC-Valencia developed a Compton camera prototype for this purpose, intending to image the Prompt Gammas emitted by the tissue during irradiation. The system detectors are composed of Lanthanum (III) bromide scintillator crystals coupled to silicon photomultipliers. After an initial characterization in the laboratory, in order to assess the system capabilities for future experiments in proton therapy centers, different tests were carried out in two facilities: PARTREC (Groningen, The Netherlands) and the CNA cyclotron (Sevilla, Spain). Characterization studies performed at PARTREC indicated that the detectors linearity was improved with respect to the previous version and an energy resolution of 5.2 % FWHM at 511 keV was achieved. Moreover, the imaging capabilities of the system were evaluated with a line source of 68Ge and a point-like source of 241Am-9Be. Images at 4.439 MeV were obtained from irradiation of a graphite target with an 18 MeV proton beam at CNA, to perform a study of the system potential to detect shifts at different intensities. In this sense, the system was able to distinguish 1 mm variations in the target position at different beam current intensities for measurement times of 1800 and 600 s.


Assuntos
Diagnóstico por Imagem , Terapia com Prótons , Método de Monte Carlo , Raios gama , Espanha
9.
Rev Gastroenterol Mex (Engl Ed) ; 88(1): 57-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36737343

RESUMO

Complementary feeding (CF) is defined as the feeding of infants that complements breastfeeding, or alternatively, feeding with a breast milk substitute, and is a process that is more than simply a guide as to what and how to introduce foods. The information provided by healthcare professionals must be up-to-date and evidence-based. Most of the recommendations that appear in the different international guidelines and position papers are widely applicable, but some must be regionalized or adapted to fit the conditions and reality of each geographic zone. The Nutrition Working Group of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) summoned a group of experts from each of the society's member countries, to develop a consensus on CF, incorporating, whenever possible, local information adapted to the reality of the region. The aim of the present document is to show the results of that endeavor. Utilizing the Delphi method, a total of 34 statements on relevant aspects of CF were evaluated, discussed, and voted upon.


Assuntos
Gastroenterologia , Lactente , Criança , Feminino , Humanos , Cocos , Consenso , América Latina , Fenômenos Fisiológicos da Nutrição do Lactente
10.
Eur J Gynaecol Oncol ; 32(3): 297-302, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797121

RESUMO

INTRODUCTION: Conservative treatment with intralesional interferon (IFN) is a therapeutic option for cervical intraepithelial neoplasia (CIN) patients of childbearing age. MATERIALS AND METHODS: The study group was made up of patients diagnosed with a high-grade lesion and treated with intralesional human recombinant IFNalpha-2b. Vaginal secretion was collected during IFNalpha-2b treatment for analysis of cytokines and viral load. RESULTS: The initial histology diagnostic was 62.5% (n = 5) with CIN 2 and 37.5% (n = 3) with CIN 3. In terms of clinical evaluation and anatomopathology, 6.5% (n = 5) had a good clinical response, while 37.5% (n = 3) had therapeutic failure. All the patients with therapeutic failure were smokers. Interleukin 6 and tumor necrosis factor-alpha concentrations were raised at the sixth application for the patient group who failed to respond to therapy compared to the responsive group (p = 0.0357). Patients with a good response exhibited a reduction in human papillomavirus viral load (p = 0.03). CONCLUSIONS: Patients that had a good response had lower concentrations of inflammatory cytokines than did non-responders.


Assuntos
Antineoplásicos/uso terapêutico , Interferon-alfa/uso terapêutico , Displasia do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Vagina/metabolismo , Adulto , Citocinas/metabolismo , DNA Viral/análise , Feminino , Citometria de Fluxo , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Pessoa de Meia-Idade , Papillomaviridae/genética , Estudos Prospectivos , Proteínas Recombinantes , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Vagina/patologia , Vagina/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
11.
Sci Rep ; 11(1): 10414, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001941

RESUMO

This work presents the first tests performed with radiochromic films and a new Micro‒Opto‒Electro-Mechanical system (MOEMS) for in situ dosimetry evaluation in radiotherapy in real time. We present a new device and methodology that overcomes the traditional limitation of time-delay in radiochromic film analysis by turning a passive detector into an active sensor. The proposed system consists mainly of an optical sensor based on light emitting diodes and photodetectors controlled by both customized electronic circuit and graphical user interface, which enables optical measurements directly. We show the first trials performed in a low‒energy proton cyclotron with this MOEMS by using gafchromic EBT3 films. Results show the feasibility of using this system for in situ dose evaluations. Further adaptation is ongoing to develop a full real‒time active detector by integrating MOEM multi‒arrays and films in flexible printed circuits. Hence, we point to improve the clinical application of radiochromic films with the aim to optimize radiotherapy treatment verifications.

12.
Rev Sci Instrum ; 92(4): 043553, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243489

RESUMO

The JET FILD is a scintillator-based Fast-ion Loss Detector optimized to measure fusion-born alpha-particle losses. This work covers its upgrade and absolute calibration in preparation for the following JET DT experiments. A fast scintillator material (TG-Green) has been installed in the JET FILD. A heater jacket is installed around the fiber bundle, responsible for transmitting the light from the scintillator plate, to anneal the fiber obscuring due to neutron damage. The JET FILD has been upgraded with a 1 Mpx camera and 2 MHz photomultiplier data acquisition hardware. Full-orbit simulations give an estimate of the shading effects on the scintillator plate of the first wall structures and provide a synthetic signal of the JET FILD. A detector instrument function enables absolute values of fast-ion losses using calibration factors. The calibration factors are made available in a shot-to-shot basis for the characterized species and energies and with corrections for the diagnostic conditions. The fast acquisition system sets the Nyquist frequency (1 MHz) above the typical mode frequencies (≈102 kHz), thus making it possible to identify MHD-induced fast-ion losses.

13.
Phys Med Biol ; 66(11)2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33853055

RESUMO

In this work we show the first microdosimetry measurements on a low energy proton beam with therapeutic-equivalent fluence rates by using the second generation of 3D-cylindrical microdetectors. The sensors belong to an improved version of a novel silicon-based 3D-microdetector design with electrodes etched inside silicon, which were manufactured at the National Microelectronics Centre (IMB-CNM, CSIC) in Spain. A new microtechnology has been employed using quasi-toroid electrodes of 25µm diameter and a depth of 20µm within the silicon bulk, resulting in a well-defined cylindrical radiation sensitive volume. These detectors were tested at the 18 MeV proton beamline of the cyclotron at the National Accelerator Centre (CNA, Spain). They were assembled into an in-house low-noise readout electronics to assess their performance at a therapeutic-equivalent fluence rate. Microdosimetry spectra of lineal energy were recorded at several proton energies starting from 18 MeV by adding 50µm thick tungsten foils gradually at the exit-window of the cyclotron external beamline, which corresponds to different depths along the Bragg curve. The experimentalyF¯values in silicon cover from (5.7 ± 0.9) to (8.5 ± 0.4) keV µm-1in the entrance to (27.4 ± 2.3) keV µm-1in the distal edge. Pulse height energy spectra were crosschecked with Monte Carlo simulations and an excellent agreement was obtained. This work demonstrates the capability of the second generation 3D-microdetectors to assess accurate microdosimetric distributions at fluence rates as high as those used in clinical centers in proton therapy.


Assuntos
Terapia com Prótons , Silício , Método de Monte Carlo , Prótons , Radiometria
14.
Healthcare (Basel) ; 9(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34828470

RESUMO

BACKGROUND: The outbreak of SARS-CoV-2 abruptly disseminated in early 2020, overcoming the capacity of health systems to respond the pandemic. It was not until the vaccines were launched worldwide that an increase in survival was observed. The objectives of this study were to analyse the characteristics of survivors and their relationship with comorbidities. We had access to a database containing information on 16,747 hospitalized patients from Mexico, all infected with SARS-CoV-2, as part of a regular follow-up. The descriptive analysis looked for clusters of either success or failure. We categorized the samples into no comorbidities, or one and up to five coexisting with the infection. We performed a logistic regression test to ascertain what factors were more influential in survival. The main variable of interest was survival associated with multimorbidity factors. The database hosted information on hospitalized patients from Mexico between March 2020 through to April 2021. Categories 2 and 3 had the largest number of patients. Survival rates were higher in categories 0 (64.8%), 1 (57.5%) and 2 (51.6%). In total, 1741 (10.5%) patients were allocated to an ICU unit. Mechanical ventilators were used on 1415 patients, corresponding to 8.76%. Survival was recorded in 9575 patients, accounting for 57.2% of the sample population. Patients without comorbidities, younger people and women were more likely to survive.

15.
Eur J Gynaecol Oncol ; 31(2): 145-50, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20527228

RESUMO

Interferons were initially described in terms of their role in blocking viral replication. They are important cytokines that act on various aspects of cell physiology. Importantly, they can affect cell proliferation or induce the differentiation of neoplastic cells. The exact way in which the interferon complex (IFN) acts on tumours is still unknown, although their use in clinical practice has been widely recommended, especially with tumours that are resistant to conventional treatments, or in situations where surgical removal might lead to a loss of organ function. IFN can be employed as a treatment for various chronic diseases, including tumours. Indeed interferon cytokines are the therapy of choice in certain situations. However, one of the difficulties yet to be overcome is the need for frequent administrations of the drug. We believe that the development of new formulations is needed to match the demand for its use in oncology treatment.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Interferon Tipo I/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias da Mama/imunologia , Feminino , Humanos , Imunidade Humoral/imunologia , Transdução de Sinais/imunologia , Neoplasias do Colo do Útero/imunologia
16.
Eur J Gynaecol Oncol ; 31(5): 522-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21061793

RESUMO

Conservative treatment with interferons (IFNs) has the advantage of preserving reproductive capacity in patients with grade 2 or 3 cervical intraepithelial neoplasia (CIN). The objective of this work was to study patients with high-grade CIN treated with intralesional IFN alpha-2b and to analyze the expression of Th1, Th2 and Th3 cytokines in cervical stroma. We observed that patients with a satisfactory response (60%) to treatment with IFN alpha-2b expressed more Th1 (IFN-gamma TNF-alpha, IL-2) cytokines, with a significant reduction in the viral load of high-risk human papillomavirus (p = 0.0313). All patients with therapeutic failure were smokers and had higher expression of cytokines Th2 (IL-4) or Th3 (TGF-beta2 and TGF-beta3).


Assuntos
Antivirais/administração & dosagem , Citocinas/metabolismo , Interferon-alfa/administração & dosagem , Displasia do Colo do Útero/tratamento farmacológico , Displasia do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Adolescente , Adulto , Feminino , Humanos , Injeções Intralesionais , Interferon alfa-2 , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Proteínas Recombinantes , Falha de Tratamento , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologia
17.
Phys Med Biol ; 65(24): 245027, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33120374

RESUMO

The IRIS group at IFIC Valencia is developing a three-layer Compton camera for treatment monitoring in proton therapy. The system is composed of three detector planes, each made of a [Formula: see text] monolithic crystal coupled to a SiPM array. Having obtained successful results with the first prototype (MACACO) that demonstrated the feasibility of the proposed technology, a second prototype (MACACO II) with improved performance has been developed, and is the subject of this work. The new system has an enhanced detector energy resolution which translates into a higher spatial resolution of the telescope. The image reconstruction method has also been improved with an accurate model of the sensitivity matrix. The device has been tested with high energy photons at the National Accelerator Centre (CNA, Seville). The tests involved a proton beam of 18 MeV impinging on a graphite target, to produce 4.4 MeV photons. Data were taken at different system positions of the telescope with the first detector at 65 and 160 mm from the target, and at different beam intensities. The measurements allowed successful reconstruction of the photon emission distribution at two target positions separated by 5 mm in different telescope configurations. This result was obtained both with data recorded in the first and second telescope planes (two interaction events) and, for the first time in beam experiments, with data recorded in the three planes (three interaction events).


Assuntos
Fótons , Terapia com Prótons/métodos , Estudos de Viabilidade , Humanos , Terapia com Prótons/instrumentação , Telescópios
18.
Phys Med Biol ; 65(17): 175004, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32885791

RESUMO

Microdosimetry has been traditionally performed through gaseous proportional counters, although in recent years different solid-state microdosimeters have been proposed and constructed for this task. In this paper, we analyze the response of solid-state devices of micrometric size with no intrinsic gain developed by CNM-CSIC (Spain). There are two major aspects of the operation of these devices that affect the reconstruction of the probability distributions and momenta of stochastic quantities related to microdosimetry. For micrometric volumes, the drift and diffusion of the charge carriers gives rise to a partial charge collection efficiency in the peripheral region of the depleted volume. This effect produces a perturbation of the reconstructed pulse height (i.e. imparted energy) distributions with respect to the actual microdosimetric distributions. The relevance of this deviation depends on the size, geometry and operating conditions of the device. On the other hand, the electronic noise from the single-event readout set-up poses a limit on the minimum detectable lineal energy when the microdosimeter size is reduced. This article addresses these issues to provide a framework on the physical constraints for the design and operation of solid-state microdosimeters.


Assuntos
Equipamentos e Provisões Elétricas , Radiometria/instrumentação , Probabilidade
19.
Appl Radiat Isot ; 66(11): 1679-82, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18572412

RESUMO

The current levels and distribution of the remaining transuranic contamination present in the terrestrial area affected by the nuclear Palomares accident have been evaluated through the determination of the Pu-isotopes and (241)Am concentrations in soils collected 35 years after the accident. In addition, after confirming that most of the contamination is present in particulate form, some bioavailability laboratory-based experiments, based on the use of single extractants, were performed as an essential step in order to study the behaviour of the Pu contamination in the soils from the affected areas.


Assuntos
Amerício/análise , Amerício/farmacocinética , Exposição Ambiental/análise , Eucariotos/metabolismo , Plutônio/análise , Plutônio/farmacocinética , Liberação Nociva de Radioativos , Poluentes Radioativos do Solo/análise , Eucariotos/química , Doses de Radiação , Monitoramento de Radiação/métodos , Espanha
20.
Appl Radiat Isot ; 66(6-7): 808-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18342525

RESUMO

This work presents an intercomparison between commercial software for alpha-particle spectrometry, Genie 2000, and the new free available software, Winalpha, developed by International Atomic Energy Agency (IAEA). In order to compare both codes, different environmental spectra containing plutonium, uranium, thorium and polonium have been analyzed, together with IAEA test alpha spectra. A statistical study was performed in order to evaluate the precision and accuracy in the analyses, and to enhance the confidence in using the software on alpha spectrometric studies.

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