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1.
Artigo em Inglês | MEDLINE | ID: mdl-38903481

RESUMO

Extreme ultraviolet spectra of highly-charged ytterbium ions produced in an electron beam ion trap at the National Institute of Standards and Technology were observed with a flat-field grazing incidence spectrometer in the wavelength region of about 4 nm-20 nm. The measured spectra were interpreted through detailed analysis by collisional-radiative modeling of the non-Maxwellian EBIT plasma. Seventy-nine new spectral lines due to intrashell (Δn = 0, n = 4) electric-dipole, magnetic-dipole, and electric-quadrupole transitions were identified in Rb-like Yb33+ through Ni-like Yb42+ ions. The effects of strong configuration interaction within the n = 4 complex on the measured spectra are discussed for a number of ionization stages.

2.
Rev Sci Instrum ; 90(12): 123107, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893849

RESUMO

We report on the design, commissioning, and initial measurements of a Transition-Edge Sensor (TES) x-ray spectrometer for the Electron Beam Ion Trap (EBIT) at the National Institute of Standards and Technology (NIST). Over the past few decades, the NIST EBIT has produced numerous studies of highly charged ions in diverse fields such as atomic physics, plasma spectroscopy, and laboratory astrophysics. The newly commissioned NIST EBIT TES Spectrometer (NETS) improves the measurement capabilities of the EBIT through a combination of high x-ray collection efficiency and resolving power. NETS utilizes 192 individual TES x-ray microcalorimeters (166/192 yield) to improve upon the collection area by a factor of ∼30 over the 4-pixel neutron transmutation doped germanium-based microcalorimeter spectrometer previously used at the NIST EBIT. The NETS microcalorimeters are optimized for the x-ray energies from roughly 500 eV to 8000 eV and achieve an energy resolution of 3.7 eV-5.0 eV over this range, a more modest (<2×) improvement over the previous microcalorimeters. Beyond this energy range, NETS can operate with various trade-offs, the most significant of which are reduced efficiency at lower energies and being limited to a subset of the pixels at higher energies. As an initial demonstration of the capabilities of NETS, we measured transitions in He-like and H-like O, Ne, and Ar as well as Ni-like W. We detail the energy calibration and data analysis techniques used to transform detector counts into x-ray spectra, a process that will be the basis for analyzing future data.

3.
Artigo em Inglês | MEDLINE | ID: mdl-29485359

RESUMO

The response of the antimicrobial compounds sulfamethoxazole (SMX) and trimethoprim (TMP) - individually and in mixtures - to ionizing radiation was investigated using laboratory prepared mixtures and a commercial pharmaceutical formulation. The residual antibacterial activity of the solutions was monitored using Staphylococcus aureus and Escherichia coli test strains. Based on antibacterial activity, SMX was more susceptible to ionizing radiation as compared to TMP. The antibacterial activity of SMX and TMP was completely eliminated at 0.2 kGy and 0.8 kGy, respectively. However, when SMX and TMP were in a mixture, the dose required to eliminate the antibacterial activity was 10 kGy, implying a synergistic antibacterial activity when these are present in mixtures. Only when the antibiotic concentration was below the Minimum Inhibitory Concentration of TMP (i.e., 2 µmol dm-3) did the antibacterial activity of the SMX and TMP mixture disappear. These results imply that the synergistic antimicrobial activity of antimicrobial compounds in pharmaceutical waste streams is a strong possibility. Therefore, antimicrobial activity assays should be included when evaluating the use of ionizing radiation technology for the remediation of pharmaceutical or municipal waste streams.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/efeitos da radiação , Radiação Ionizante , Sulfametoxazol/farmacologia , Trimetoprima/farmacologia , Antibacterianos/farmacologia , Antibacterianos/efeitos da radiação , Anti-Infecciosos/farmacologia , Anti-Infecciosos/efeitos da radiação , Bactérias/crescimento & desenvolvimento , Análise da Demanda Biológica de Oxigênio , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação , Sulfametoxazol/efeitos da radiação , Trimetoprima/efeitos da radiação , Combinação Trimetoprima e Sulfametoxazol
4.
Artigo em Inglês | MEDLINE | ID: mdl-32201753

RESUMO

The difference in the mean-square nuclear charge radius of xenon isotopes was measured utilizing a method based on extreme ultraviolet spectroscopy of highly charged Na-like ions. The isotope shift of the Na-like D1 (3s 2 S 1/2 - 3p 2 P 1/2) transition between the 124Xe and 136Xe isotopes was experimentally determined using the electron-beam ion-trap facility at the National Institute of Standards and Technology. The mass-shift and the field-shift coefficients were calculated with enhanced precision by the relativistic many-body perturbation theory and multiconfiguration Dirac-Hartree-Fock method. The mean-square nuclear charge radius difference was found to be δ〈r 2〉136,124 = 0.269(42) fm2. Our result has smaller uncertainty than previous experimental results and agrees with the literature values.

6.
Phys Rev Lett ; 109(15): 153001, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23102303

RESUMO

We report a new test of quantum electrodynamics (QED) for the w (1s2p(1)P(1)→1s(2)(1)S(0)) x-ray resonance line transition energy in heliumlike titanium. This measurement is one of few sensitive to two-electron QED contributions. Systematic errors such as Doppler shifts are minimized in our experiment by trapping and stripping Ti atoms in an electron beam ion trap and by applying absolute wavelength standards to calibrate the dispersion function of a curved-crystal spectrometer. We also report a more general systematic discrepancy between QED theory and experiment for the w transition energy in heliumlike ions for Z>20. When all of the data available in the literature for Z=16-92 are taken into account, the divergence is seen to grow as approximately Z(3) with a statistical significance on the coefficient that rises to the level of 5 standard deviations. Our result for titanium alone, 4749.85(7) eV for the w line, deviates from the most recent ab initio prediction by 3 times our experimental uncertainty and by more than 10 times the currently estimated uncertainty in the theoretical prediction.

7.
J Biol Phys ; 36(2): 207-20, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19795216

RESUMO

The present work aims to characterize the dynamical behavior of proteins immersed in bio-preserving liquids and glasses. For this purpose, the protein dUTPase was chosen, while the selected solvents were glycerol, a triol, and some homologous disaccharides, i.e., trehalose, maltose, and sucrose, which are known to be very effective bio-preserving agents. The results highlight that the disaccharides show a slowing down effect on the water dynamics, which is stronger for trehalose than in the case of the other disaccharides. Furthermore, a characterization of the medium which hosts the protein is performed by using an operative definition of fragility based on the mean square displacement extracted by elastic incoherent neutron scattering, which is directly connected to Angell's kinetic fragility based on the viscosity. Finally, a study of the dynamics of the protein sequestered within the solvents is performed. The result shows that the protein dynamics is coupled with that of the surrounding matrix.

8.
J Hazard Mater ; 172(2-3): 1185-92, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19699577

RESUMO

Polyphenols, like gallic acid (GA) released in the environment in larger amount, by inducing some unwanted oxidations, may constitute environmental hazard: their concentration in wastewater should be controlled. Radiolytic degradation of GA was investigated by pulse radiolysis and final product techniques in dilute aqueous solution. Subsidiary measurements were made with 3,4,5-trimethoxybenzoic acid (TMBA) and 3,4,5-trihydroxy methylbenzoate (MGA). The hydroxyl radical and hydrogen atom intermediates of water radiolysis react with the solute molecules yielding cyclohexadienyl radicals. The radicals formed in GA and MGA solutions in acid/base catalyzed water elimination decay to phenoxyl radicals. This reaction is not observed in TMBA solution. The hydrated electron intermediate of water decomposition adds to the carbonyl oxygen, the anion thus formed protonates on the ring forming cyclohexadienyl radical or on the carbonyl group forming carbonyl centred radical. The GA intermediates formed during reaction with primary water radicals in presence of oxygen transform to non-aromatic molecules, e.g., to aliphatic carboxylic acids.


Assuntos
Ácido Gálico/efeitos da radiação , Substâncias Perigosas , Radiólise de Impulso/métodos , Flavonoides , Radicais Livres/química , Ácido Gálico/química , Resíduos Industriais/prevenção & controle , Fenóis , Polifenóis , Soluções , Água , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação
9.
Water Res ; 41(12): 2533-40, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17466358

RESUMO

The mechanism of high-energy radiation induced degradation of H-acid (4-amino-5-hydroxynaphthalene-2,7-disulphonic acid, (I)) and its derivative, 4-hydroxynaphthalene-2,7-disulphonic acid (II) (central parts of a large number of azo dyes), was investigated in aqueous solutions. These compounds can be efficiently destroyed by the (*)OH and hydrated electron intermediates produced during water radiolysis. As the first step of degradation mainly cyclohexadienyl-type radicals form, however, with I H-atom elimination from the NH(2) group is also observed yielding anilino-type radicals. Both the cyclohexadienyl and the anilino-type radicals decay on the millisecond timescale. In the (*)OH reactions as stable products hydroxylated molecules and quinone-type compounds form. These molecules by further decomposition of the ring structure transform to open chain molecules. In the case of hydrated electron, the primarily formed products have absorption spectra shifted to the low-wavelength region indicating the destruction of at least one of the aromatic rings.


Assuntos
Corantes/efeitos da radiação , Raios gama , Naftalenossulfonatos/efeitos da radiação , Poluentes Químicos da Água/efeitos da radiação , Corantes/química , Radical Hidroxila/química , Naftalenossulfonatos/química , Soluções , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos
10.
BMC Health Serv Res ; 6: 50, 2006 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-16608510

RESUMO

BACKGROUND: Is the implementation of Quality Management (QM) in health care proceeding satisfactorily and can national health care policies influence the implementation process? Policymakers and researchers in a country need to know the answer to this question. Cross country comparisons can reveal whether sufficient progress is being made and how this can be stimulated. The objective of the study was to investigate agreement and disparities in the implementation of QMS between The Netherlands, Hungary and Finland with respect to the evaluation model used and the national policy strategy of the three countries. METHODS: The study has a cross sectional design, based on measurements in 2000. Empirical data about QM-activities in hospitals were gathered by a self-administered questionnaire. The questionnaires were answered by the directors of the hospitals or the quality coordinators. The analyses are based on data from 101 hospitals in the Netherlands, 116 hospitals in Hungary and 59 hospitals in Finland. Outcome measures are the developmental stage of the Quality Management System (QMS), the development within five focal areas, and distinct QM-activities which were listed in the questionnaire. RESULTS: A mean of 22 QM-activities per hospital was found in the Netherlands and Finland versus 20 QM-activities in Hungarian hospitals. Only a small number of hospitals has already implemented a QMS (4% in The Netherlands,0% in Hungary and 3% in Finland). More hospitals in the Netherlands are concentrating on quality documents, whereas Finnish hospitals are concentrating on training in QM and guidelines. Cyclic quality improvement activities have been developed in the three countries, but in most hospitals the results were not used for improvements. All three countries pay hardly any attention to patient participation. CONCLUSION: The study demonstrates that the implementation of QM-activities can be measured at national level and that differences between countries can be assessed. The hypothesis that governmental legislation or financial reimbursement can stimulate the implementation of QM-activities, more than voluntary recommendations, could not be confirmed. However, the results show that specific obligations can stimulate the implementation of QM-activities more than general, framework legislation.


Assuntos
Difusão de Inovações , Implementação de Plano de Saúde/métodos , Administração Hospitalar/normas , Programas Nacionais de Saúde/organização & administração , Gestão da Qualidade Total/estatística & dados numéricos , Comparação Transcultural , Estudos Transversais , Pesquisa Empírica , Finlândia , Implementação de Plano de Saúde/estatística & dados numéricos , Humanos , Hungria , Países Baixos , Política Organizacional , Técnicas de Planejamento , Inquéritos e Questionários
11.
Clin Endocrinol (Oxf) ; 60(4): 508-15, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15049967

RESUMO

OBJECTIVE: The fluctuations in sex hormone levels at the beginning of adolescence, in the perimenopausal period, during pregnancy or during the use of oral contraceptives can precipitate oedematous attacks in hereditary angioneurotic oedema (HANO). Attacks usually disappear after the onset of menopause. This study was undertaken to establish any relationship between the serum levels of sex hormones and the incidence of HANO attacks. PATIENTS AND MEASUREMENTS: Serum levels of LH, FSH, progesterone, oestradiol, testosterone, PRL and SHBG were measured in 78 patients [mean age 30.3 years (range 4-70 years)] with HANO. A questionnaire was used to explore the medical history of adult patients to characterize the evolution and the characteristics of attacks. RESULTS: The number of attacks was significantly higher [odds ratio (OR) 6.36 (1.31-30.81); P = 0.022] in females with high progesterone levels (> or = 4 nmol/l), irrespective of age, menstrual cycle and danazol dose. The OR was even higher [13.4 (2.2-81.4); P = 0.005] when only subcutaneous attacks were considered. Multiple logistic regression analysis demonstrated a significantly lower attack frequency during 1-year follow-up in patients with a higher (40 nmol/l) SHBG level (OR 0.25 (0.07-0.90); P = 0.034). This difference existed independently of age and danazol dose. CONCLUSION: In view of these results, the monitoring of progesterone and SHBG levels can prove useful in the prediction of attacks in hereditary angioneurotic oedema.


Assuntos
Angioedema/sangue , Hormônios Esteroides Gonadais/sangue , Adolescente , Adulto , Idoso , Angioedema/tratamento farmacológico , Biomarcadores/sangue , Criança , Pré-Escolar , Danazol/uso terapêutico , Estradiol/sangue , Antagonistas de Estrogênios/uso terapêutico , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Modelos Logísticos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Progesterona/sangue , Prolactina/sangue , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(4 Pt 2): 046409, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308958

RESUMO

Spectra of highly charged Kr ions, produced in an electron-beam ion trap (EBIT), have been recorded in a broad x-ray energy band (0.3 keV to 4 keV) with a microcalorimeter detector. Most of the spectral lines have been identified as transitions of B- to Al-like Kr. The transition energies have been determined with 0.2% uncertainty. A semi-empirical EBIT plasma model has been created to calculate a synthetic spectrum of highly charged Kr and to determine a charge state distribution of Kr ions inside the EBIT.

13.
Arzneimittelforschung ; 50(12): 1071-7, 2000 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-11190771

RESUMO

There are some experimental and clinical results regarding blood vessel protective properties of magnesium orotate (CAS 27067-77-2) till now. The goal of the present investigation was to verify the therapeutical efficacy of magnesium orotate vs. its singular components in cholesterol fed rabbits. Besides, the blood-lipid concentrations (LDL as risk factor for atherosclerosis and HDL as negative risk factor) were analyzed in relation to pathomorphological changes in the aortic blood vessel wall. The results of our experiments in New Zealand rabbits support the assumption that orotic acid and especially magnesium orotate influence the lipid level and/or the LDL/HDL-quotient in a favorable way and that they decrease the interaction between monocytes/macrophages and the endothelium of the blood vessels. Consequently, the plaque formation will be decreased in a clinically relevant manner.


Assuntos
Anticolesterolemiantes/uso terapêutico , Arteriosclerose/patologia , Arteriosclerose/prevenção & controle , Vasos Sanguíneos/patologia , Ácido Orótico/análogos & derivados , Ácido Orótico/uso terapêutico , Animais , Vasos Sanguíneos/ultraestrutura , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta Aterogênica , Progressão da Doença , Endotélio Vascular/patologia , Masculino , Microscopia Eletrônica , Coelhos
14.
Orv Hetil ; 138(36 Suppl 2): 2276-80, 1997 Sep 07.
Artigo em Húngaro | MEDLINE | ID: mdl-9340570

RESUMO

Heart and blood vessel disease are one of the leading causes of death, so their prevention and therapy are very important. In the present study the effects of magnesium chloride, magnesium orotate and orotic acid were tested. New Zealand rabbits were fed with enriched (2%) cholesterol diet during 112 days: starting with day 56 all rabbits were treated with MgCl2, Mg-orotate or orotic acid (orally). Aortas, coronaries, renal and femoral arteries were removed and evaluated by morphological and morphometric methods. Atherosclerotic alterations in each vessel could be influenced moderately by Mg-chloride, quite well by orotic acid and excellently by Mg-orotate. From these results one can conclude that orotic acid and Mg-orotate have a beneficial effect in the prevention and therapy of heart and vessels diseases.


Assuntos
Arteriosclerose/etiologia , Colesterol na Dieta/administração & dosagem , Dieta Aterogênica , Ácido Orótico/administração & dosagem , Animais , Arteriosclerose/diagnóstico por imagem , Arteriosclerose/patologia , Arteriosclerose/prevenção & controle , Modelos Animais de Doenças , Hipercolesterolemia/prevenção & controle , Cloreto de Magnésio , Coelhos , Radiografia
17.
Orv Hetil ; 137(9): 455-9, 1996 Mar 03.
Artigo em Húngaro | MEDLINE | ID: mdl-8714038

RESUMO

Platelet aggregation was examined in 43 patients after ischemic stroke and in 16 healthy subjects using multiparametric aggregation index (MAI). The value of MAI was significantly higher in stroke patients (3.15 in patients and 0.92 l/mumol in controls, p < 0.0001). Patients who had increased MAI (n = 26) were treated with a daily dose of 100 mg acetilsalicylic acid (ASA). Platelet activity was measured before and on the 7th and 28th day of treatment measuring three parameters: MAI, spontaneous dysaggregation and collagen induced aggregation. All 3 methods showed a significant decrease in platelet aggregation on the 7th day of treatment, but further changes were not found on the 28th day. Serum levels of thromboxane-A2 (TXA2) and prostacycline (PGI2) metabolites (TXB2 and 6-keto-prostaglandin-F1 alpha) were determined before and on the 28th day of treatment. The effect of 100 mg ASA per day proved to be selective: comparing the serum levels before and after treatment, a significant decrease of TXB2 concentration was found without changes in the concentration of 6-keto-prostaglandin-F1 alpha. Evaluating MAI and the value of dysaggregation might reflect ineffectiveness of antiplatelet therapy in patients not responding to a daily dose of 100 mg of ASA. For these patients the increase of the daily dose of ASA, or changing to another antiplatelet drug might be recommended.


Assuntos
Aspirina/uso terapêutico , Isquemia Encefálica/complicações , Transtornos Cerebrovasculares/etiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Aspirina/administração & dosagem , Testes de Coagulação Sanguínea , Isquemia Encefálica/sangue , Transtornos Cerebrovasculares/sangue , Transtornos Cerebrovasculares/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Prostaglandinas F/sangue , Tromboxano A2/sangue , Tromboxano B2/sangue
18.
Arzneimittelforschung ; 45(8): 836-42, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7575742

RESUMO

Heart and blood vessel diseases are one of the leading causes of death, so their prevention and therapy are very important. In the present study the effects of magnesium chloride, magnesium orotate and orotic acid were tested. New Zealand rabbits were fed with enriched (2%) cholesterol diet during 112 days; starting with day 56 all rabbits were treated with MgCl2, Mg-orotate or orotic acid (orally). Aortas, coronaries, renal and femoral arteries were removed and evaluated by morphological and morphometric methods. Atherosclerotic alterations in each vessel could be influenced moderately by Mg-chloride, quite well by orotic acid and excellently by Mg-orotate. From these results one can conclude that orotic acid and Mg-orotate have a beneficial effect in the prevention and therapy of heart and vessels diseases.


Assuntos
Anticolesterolemiantes/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/patologia , Animais , Aorta/patologia , Colesterol na Dieta/farmacologia , Vasos Coronários/patologia , Artéria Femoral/patologia , Cloreto de Magnésio/farmacologia , Masculino , Ácido Orótico/análogos & derivados , Ácido Orótico/uso terapêutico , Coelhos , Artéria Renal/patologia
20.
Int J Parasitol ; 24(6): 871-6, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7982749

RESUMO

High responder (HR) and low responder (LR) lines of sheep of the Hungarian Merino breed were selected by using faecal egg counts (epg) as parameter of responsiveness after double artificial Haemonchus contortus test infections. A total of 81 lambs born to assortative matings of HR rams with HR ewes and LR rams with LR ewes, as well as 28 control lambs from unselected parent sheep, were studied to estimate the heritability of responsiveness. A relatively high level of heritability (h2 = 0.49 +/- 0.17) was observed. A comparative assessment of responder classification carried out by two subsequent and distinct H. contortus and Trichostrongylus colubriformis infections revealed a remarkable degree of agreement: identical results in 69.7% and marginal differences in 23.2% of 99 animals. These results suggest that by selecting sheep for high responsiveness to a certain species of nematodes, one can also achieve a substantial improvement of resistance against a wide range of other nematode species.


Assuntos
Hemoncose/genética , Doenças dos Ovinos , Animais , Cruzamentos Genéticos , Feminino , Hemoncose/fisiopatologia , Masculino , Análise Multivariada , Ovinos
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