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1.
BMC Public Health ; 18(1): 1182, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340630

RESUMO

BACKGROUND: Nudging interventions have lately been widely adopted by policy makers to increase the welfare of society and to help citizens make better choices. Hence, it has become important to understand the conditions under which they are approved. While most research has looked into whether professionals approve of nudging interventions, surprisingly the opinion of the target group has been widely ignored. This study investigated citizens' level of approval of nudging in the realm of healthy eating promotion, as well as its boundary conditions. METHODS: Participants (N = 1441) from the US and seven European countries were probed for their level of approval of nudges. Moreover, we investigated whether these levels of approval were dependent on the level of intrusiveness of the nudge and on the type and trustworthiness of the source (policy makers, experts, industry) implementing the nudge. RESULTS: People revealed moderate to high levels of approval with nudging across all countries. Intrusiveness and nudging approval were negatively associated. Nudges implemented by experts received more approval than those by policy makers. In general, approval increased with the trustworthiness of the source. CONCLUSIONS: These results provide information for European and American policy makers considering using nudging in their policy repertoire.


Assuntos
Dieta Saudável , Promoção da Saúde/métodos , Opinião Pública , Adulto , Comportamento de Escolha , Dieta Saudável/psicologia , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Confiança , Estados Unidos
2.
Appetite ; 106: 2-12, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-26407803

RESUMO

Food manufacturers and policy makers have been tailoring food product ingredient information to consumers' self-reported preference for natural products and concerns over food additives. Yet, the influence of this ingredient information on consumers remains inconclusive. The current study aimed at examining the first step in such influence, which is consumers' attention to ingredient information on food product packaging. Employing the choice-blindness paradigm, the current study assessed whether participants would detect a covertly made change to the naturalness of ingredient list throughout a product evaluation procedure. Results revealed that only few consumers detected the change on the ingredient lists. Detection was improved when consumers were instructed to judge the naturalness of the product as compared to evaluating the product in general. These findings challenge consumers' self-reported use of ingredient lists as a source of information throughout product evaluations. While most consumers do not attend to ingredient information, this tendency can be slightly improved by prompting their consideration of naturalness. Future research should investigate the reasons for consumers' inattention to ingredient information and develop more effective strategies for conveying information to consumers.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Ingredientes de Alimentos , Rotulagem de Alimentos , Embalagem de Alimentos/métodos , Preferências Alimentares/psicologia , Adulto , Atenção , Feminino , Alimentos Orgânicos , Humanos , Masculino , Países Baixos
3.
Phys Rev Lett ; 112(7): 072501, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579591

RESUMO

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A=124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

4.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341719

RESUMO

We present an inversion method capable of robustly unfolding MeV x-ray spectra from filter stack spectrometer (FSS) data without requiring an a priori specification of a spectral shape or arbitrary termination of the algorithm. Our inversion method is based upon the perturbative minimization (PM) algorithm, which has previously been shown to be capable of unfolding x-ray transmission data, albeit for a limited regime in which the x-ray mass attenuation coefficient of the filter material increases monotonically with x-ray energy. Our inversion method improves upon the PM algorithm through regular smoothing of the candidate spectrum and by adding stochasticity to the search. With these additions, the inversion method does not require a physics model for an initial guess, fitting, or user-selected termination of the search. Instead, the only assumption made by the inversion method is that the x-ray spectrum should be near a smooth curve. Testing with synthetic data shows that the inversion method can successfully recover the primary large-scale features of MeV x-ray spectra, including the number of x-rays in energy bins of several-MeV widths to within 10%. Fine-scale features, however, are more difficult to recover accurately. Examples of unfolding experimental FSS data obtained at the Texas Petawatt Laser Facility and the OMEGA EP laser facility are also presented.

5.
Phys Rev Lett ; 111(24): 242503, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24483648

RESUMO

The E1 strength distribution in 68Ni has been investigated using Coulomb excitation in inverse kinematics at the R3B-LAND setup and by measuring the invariant mass in the one- and two-neutron decay channels. The giant dipole resonance and a low-lying peak (pygmy dipole resonance) have been observed at 17.1(2) and 9.55(17) MeV, respectively. The measured dipole polarizability is compared to relativistic random phase approximation calculations yielding a neutron-skin thickness of 0.17(2) fm. A method and analysis applicable to neutron-rich nuclei has been developed, allowing for a precise determination of neutron skins in nuclei as a function of neutron excess.

6.
Nat Commun ; 13(1): 54, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013209

RESUMO

Intense lasers can accelerate electrons to very high energy over a short distance. Such compact accelerators have several potential applications including fast ignition, high energy physics, and radiography. Among the various schemes of laser-based electron acceleration, vacuum laser acceleration has the merits of super-high acceleration gradient and great simplicity. Yet its realization has been difficult because injecting free electrons into the fast-oscillating laser field is not trivial. Here we demonstrate free-electron injection and subsequent vacuum laser acceleration of electrons up to 20 MeV using the relativistic transparency effect. When a high-contrast intense laser drives a thin solid foil, electrons from the dense opaque plasma are first accelerated to near-light speed by the standing laser wave in front of the solid foil and subsequently injected into the transmitted laser field as the opaque plasma becomes relativistically transparent. It is possible to further optimize the electron injection/acceleration by manipulating the laser polarization, incident angle, and temporal pulse shaping. Our result also sheds light on the fundamental relativistic transparency process, crucial for producing secondary particle and light sources.

7.
J Asthma ; 46(8): 835-40, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19863289

RESUMO

OBJECTIVE: The current study investigated whether differences existed in health-related quality of life between individuals who self-identified as having childhood-onset asthma and individuals without a chronic illness. Additionally, the relationship between perceived illness intrusiveness and illness uncertainty to health-related quality of life was explored. METHODS: College undergraduates at least 18 years of age who self-identified as having childhood asthma were randomly matched by age and gender to healthy control participants. Participants completed a demographic form, the Mishel Uncertainty in Illness Scale-Community Form, the Illness Intrusiveness Scale, and the SF-36 Health Survey, a measure of health-related quality of life. RESULTS: Participants with asthma had significantly lower scores on the total and mental health-related quality of life scales than did healthy control subjects. There were no significant differences between self-identified participants with asthma and matched healthy control subjects on physical health-related quality of life scales. Illness intrusiveness was not related to either the physical (e.g., physical functioning, general health) or mental health-related quality of life. Higher levels of illness uncertainty were significantly related to higher levels of mental health-related quality of life (e.g., vitality, mental health). In addition, participants with asthma scored significantly lower than healthy controls on the social functioning and role-emotional subscales. CONCLUSION: The current study adds to the extant literature by examining the relationships between illness intrusiveness, illness uncertainty, and health-related quality of life among a young adult population. College students with asthma appear to be at risk for diminished quality of life compared to a healthy comparison group. Further examination of various domains of health-related quality of life among older adolescents and young adults with childhood asthma is needed.


Assuntos
Asma/fisiopatologia , Asma/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Qualidade de Vida , Estudantes , Universidades , Adulto Jovem
8.
FEBS Lett ; 427(2): 305-8, 1998 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-9607334

RESUMO

Antioxidant activity of carotenoids in multilamellar liposomes assayed by inhibition of formation of thiobarbituric acid-reactive substances was in the ranking: lycopene> alpha-tocopherol > alpha-carotene > beta-cryptoxanthin > zeaxanthin = beta-carotene > lutein. Mixtures of carotenoids were more effective than the single compounds. This synergistic effect was most pronounced when lycopene or lutein was present. The superior protection of mixtures may be related to specific positioning of different carotenoids in membranes.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Luteína/farmacologia , Sinergismo Farmacológico , Lipossomos/metabolismo , Licopeno , Tiobarbitúricos , Vitamina E/farmacologia
9.
Free Radic Res ; 33(6): 801-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11237102

RESUMO

Unilamellar liposomes are used as a simple two-compartment model to study the interaction of antioxidants. The vesicle membrane can be loaded with lipophilic compounds such as carotenoids or tocopherols, and the aqueous core space with hydrophilic substances like glutathione (GSH) ascorbate, mimicking the interphase between an aqueous compartment of a cell and its surrounding membrane. Unilamellar liposomes were used to investigate the interaction of GSH with the carotenoids lutein, beta-carotene and lycopene in preventing lipid peroxidation. Lipid peroxidation was initiated with 2,2'-azobis-[2,4-dimethylvaleronitrile] (AMVN). Malondialdehyde (MDA) formation was measured as an indicator of oxidation; additionally, the loss of GSH was followed. In liposomes without added antioxidant, MDA levels of 119 +/- 6 nmol/mg phospholipid were detected after incubation with AMVN for 2 h at 37 degrees C. Considerably lower levels of 57 +/- 8 nmol MDA/mg phospholipid were found when the liposomal vesicles had been loaded with GSH. Upon incorporation of beta-carotene, lycopene or lutein, the resistance of unilamellar liposomes towards lipid peroxidation was further modified. An optimal further protection was observed with 0.02 nmol beta-carotene/mg phospholipid or 0.06 nmol lycopene/mg phospholipid. At higher levels both these carotenoids exhibited prooxidant effects. Lutein inhibited lipid peroxidation in a dose-dependent manner between 0.02 and 2.6 nmol/mg phospholipid. With increasing levels of lycopene and lutein the consumption of encapsulated GSH decreased moderately, and high levels of beta-carotene led to a more pronounced loss of GSH. The data demonstrate that interactions between GSH and carotenoids may improve resistance of biological membranes towards lipid peroxidation. Different carotenoids exhibit specific properties, and the level for optimal protection varies between the carotenoids.


Assuntos
Antioxidantes/química , Carotenoides/química , Glutationa/química , Lipossomos/química , Antioxidantes/farmacologia , Compostos Azo/farmacologia , Carotenoides/análise , Fenômenos Químicos , Físico-Química , Glutationa/análise , Peroxidação de Lipídeos , Luteína/análise , Luteína/química , Licopeno , Malondialdeído/química , Microscopia Eletrônica , Nitrilas/farmacologia , Oxidantes/farmacologia , beta Caroteno/análise , beta Caroteno/química
10.
Int J Nurs Stud ; 51(5): 703-16, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24161740

RESUMO

BACKGROUND: Nurses' clinical judgement plays a vital role in pressure ulcer risk assessment, but evidence is lacking which patient characteristics are important for nurses' perception of patients' risk exposure. OBJECTIVES: To explore which patient characteristics nurses employ when assessing pressure ulcer risk without use of a risk assessment scale. DESIGN: Mixed methods design triangulating observational data from the control group of a quasi-experimental trial and data from semi-structured interviews with nurses. SETTING: Two traumatological wards at a university hospital. PARTICIPANTS: Quantitative data: A consecutive sample of 106 patients matching the eligibility criteria (age ≥ 18 years, no pressure ulcers category ≥ 2 at admission and ≥ 5 days expected length of stay). Qualitative data: A purposive sample of 16 nurses. METHODS: Quantitative data: Predictor variables for pressure ulcer risk were measured by study assistants at the bedside each second day. Concurrently, nurses documented their clinical judgement on patients' pressure ulcer risk by means of a 4-step global judgement scale. Bivariate correlations between predictor variables and nurses' risk estimates were established. Qualitative data: In interviews, nurses were asked to assess fictitious patients' pressure ulcer risk and to justify their risk estimates. Patient characteristics perceived as relevant for nurses' judements were thematically clustered. Triangulation: Firstly, predictors of nurses' risk estimates identified in bivariate analysis were cross-mapped with interview findings. Secondly, three models to predict nurses' risk estimates underwent multiple linear regression analysis. RESULTS: Nurses consider multiple patient characteristics for pressure ulcer risk assessment, but regard some conditions more important than others. Triangulation showed that these are measures reflecting patients' exposure to pressure or overall care dependency. Qualitative data furthermore indicate that nurses are likely to trade off risk-enhancing conditions against conditions perceived to be protective. Here, patients' mental capabilities like willingness to engage in one owns care seem to be particularly important. Due to missing information on these variables in the quantitative data, they could not be incorporated into triangulation. CONCLUSIONS: Nurses' clinical judgement draws on well-known aetiological factors, and tends to expand conditions covered by risk assessment scales. Patients' care dependency and self-care abilities seem to be core concepts for nurses' risk assessment.


Assuntos
Avaliação em Enfermagem , Úlcera por Pressão/enfermagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/prevenção & controle , Medição de Risco
12.
Arch Biochem Biophys ; 391(2): 160-4, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11437346

RESUMO

Lutein and zeaxanthin are the predominant carotenoids in the human macula lutea. Epidemiological data suggest that an increased intake of a lutein-rich diet correlates with a diminished risk for age-related macular degeneration, a major cause of impaired vision in the elderly. Filtering of blue light has been proposed as a possible mechanism of protection. Here, the blue light filter efficacy of carotenoids was investigated in unilamellar liposomes loaded in the hydrophilic core space with a fluorescent dye, Lucifer yellow, excitable by blue light. Carotenoids were incorporated into the lipophilic membrane. Fluorescence emission in carotenoid-containing liposomes was lower than in carotenoid-free controls when exposed to blue light, indicating a filter effect. Filter efficacy was in the order lutein > zeaxanthin > beta-carotene > lycopene. Some of the difference in blue light filter efficacy of carotenoids is attributable to differences in extinction coefficients, and a major further contribution is suggested to be related to the orientation of the incorporated molecules in the liposomal membrane.


Assuntos
Lipossomos/metabolismo , Luteína/metabolismo , Macula Lutea/metabolismo , beta Caroteno/metabolismo , Filtração , Humanos , Luz , Macula Lutea/efeitos da radiação , Análise Espectral , Xantofilas , Zeaxantinas , beta Caroteno/análogos & derivados
13.
Phys Rev Lett ; 93(7): 072501, 2004 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-15324228

RESUMO

A new experimental approach is introduced to investigate the relaxation of the nuclear deformation degrees of freedom. Highly excited fissioning systems with compact shapes and low angular momenta are produced in peripheral relativistic heavy-ion collisions. Both fission fragments are identified in atomic number. Fission cross sections and fission-fragment element distributions are determined as a function of the fissioning element. From the comparison of these new observables with a nuclear-reaction code a value for the transient time is deduced.

14.
Phys Rev Lett ; 88(4): 041101, 2002 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-11801101

RESUMO

We measured the 7Be(p,gamma)8B cross section from E(c.m.) = 186 to 1200 keV, with a statistical-plus-systematic precision per point of better than +/-5%. All important systematic errors were measured including 8B backscattering losses. We obtain S17(0) = 22.3+/-0.7(expt)+/-0.5(theor) eV b from our data at E(c.m.)< or =300 keV and the theory of Descouvemont and Baye.

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