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1.
Nature ; 609(7925): 41-45, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36045235

RESUMEN

When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.

2.
Phys Rev Lett ; 132(16): 162501, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701469

RESUMEN

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

3.
Faraday Discuss ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39058290

RESUMEN

Using a combination of liquid-phase X-ray spectroscopy experiments and small-scale calculations we have gained new insights into the speciation of halozincate anions in ionic liquids (ILs). Both core and valence X-ray photoelectron spectroscopy (XPS) experiments were performed directly on the liquid-phase ILs, supplemented by Zn 1s X-ray absorption near edge structure (XANES) spectroscopy. Density functional theory (DFT) calculations were carried out on both 1- and 2- halozincate anions, in both a generalised solvation model SMD (Solvation Model based on Density) and the gas phase, to give XP spectra and total energy differences; time-dependent DFT was used to calculate XANES spectra. Speciation judgements were made using a combination of the shape and width of the experimental spectra, and visual matches to the calculated spectra. For 2- halozincate anions, excellent matches were found between the experimental and calculated XP spectra, clearly showing that only 2- halozincate anions were present at all zinc halide mole fractions, x, studied. At specific values of x (0.33, 0.50, 0.60) only one halozincate anion was present; equilibria of different halozincate anions at those values of x were not observed. All findings show that chlorozincate anion and bromozincate anion speciation matched at the same x. Based on the results, predictions are made of the halozincate anion speciation for all values of x up to 0.67. Caution is advised when using differences in calculated total energies obtained from DFT to judge halozincate anion speciation, even when the SMD was employed, as predictions based on total energy differences did not always match the findings from the experimental and calculated spectra. Our findings clearly establish that the combination of high-quality experimental data from multiple spectroscopies and a wide range of calculated structures are essential to have high confidence in halozincate anion speciation identification.

4.
Clin Radiol ; 79(2): 117-123, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37989667

RESUMEN

AIM: To evaluate variation in magnetic resonance imaging (MRI) technique and reporting of rectal cancer staging examinations across the UK. MATERIALS AND METHODS: A retrospective, multi-centre audit was undertaken of imaging protocols and information documented within consecutive MRI rectal cancer reports between March 2020 and August 2021, which were compared against American and European guidelines. Inclusion criteria included histologically proven rectal adenocarcinoma and baseline staging MRI rectum only. RESULTS: Fully anonymised data from 924 MRI reports by 78 radiologists at 24 centres were evaluated. Thirty-two per cent of radiologists used template reporting, but these reports offered superior documentation of 13 out of 18 key tumour features compared to free-text reports including T-stage, relation to peritoneal reflection and mesorectal fascia (MRF), nodal status, and presence of extramural venous invasion (EMVI; p<0.027 in each). There was no significant differences in the remaining five features. Across all tumour locations, the tumour relationship to the MRF, the presence of EMVI, and the presence of tumour deposits were reported in 79.5%, 85.6%, and 44% of cases, respectively, and tumour, nodal, and distant metastatic stage documented in 94.4%, 97.7%, and 78.3%. In low rectal tumours, the relationship to the anal sphincter complex was reported in only 54.6%. CONCLUSION: Considerable variation exists in rectal cancer MRI acquisition and reporting in this sample of UK centres. Inclusion of key radiological features in reports must be improved for risk stratification and treatment decisions. Template reporting is superior to free-text reporting. Routine adoption of standardised radiology practices should now be considered to improve standards to facilitate personalised precision treatment for patients to improve outcomes.


Asunto(s)
Radiología , Neoplasias del Recto , Humanos , Estudios Retrospectivos , Neoplasias del Recto/patología , Imagen por Resonancia Magnética/métodos , Reino Unido , Estadificación de Neoplasias , Invasividad Neoplásica/patología
5.
Public Health ; 215: 17-26, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36608601

RESUMEN

OBJECTIVES: This study systematically reviewed scientific evidence regarding the impact of economic growth on physical activity (PA) and sedentary behaviors. METHODS: A keyword and reference search was conducted in PubMed, Web of Science, Cochrane Library, Scopus, and EBSCO from the inception of an electronic bibliographic database to November 2021. Studies that met all of the following criteria were included in the review: (1) study designs: observational studies; (2) study subjects: people of all ages; (3) exposure: macroeconomic growth; (4) outcomes: PA or sedentary behaviors/sitting time. RESULTS: 15 studies were identified. Eight among 12 studies found economic growth positively associated with at least one domain/measure of PA, whereas the remaining four found an inverse relationship. One of two studies examined the association of economic growth and physical inactivity found a positive relationship, while another found no significant relationship. Four studies examined the associations between economic growth and sedentary behaviors, and the results were inconclusive. The impact of economic growth on PA is through three main pathways-(a) building and maintaining parks and green spaces, (b) adoption of the modern workplace and high technology, and (c) motorized transportation. CONCLUSION: Building and maintaining parks and green spaces can effectively promote leisure time physical activity and active commute in developed countries, whereas promoting workplace and transportation-related PA could be prioritized in developing nations. Future research calls for longitudinal study design and further exploration of macro-environmental factors. Policymakers and stakeholders should be informed about the potential PA reduction resulting from economic growth and develop preventive strategies to alleviate the problem.


Asunto(s)
Desarrollo Económico , Conducta Sedentaria , Humanos , Estudios Longitudinales , Ejercicio Físico , Actividad Motora
6.
Phys Rev Lett ; 129(4): 042501, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35939025

RESUMEN

We report a precise measurement of the parity-violating (PV) asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{48}Ca. We measure A_{PV}=2668±106(stat)±40(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(q=0.8733 fm^{-1})=0.1304±0.0052(stat)±0.0020(syst) and the charge minus the weak form factor F_{ch}-F_{W}=0.0277±0.0055. The resulting neutron skin thickness R_{n}-R_{p}=0.121±0.026(exp)±0.024(model) fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter.

7.
Phys Rev Lett ; 128(14): 142501, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35476486

RESUMEN

We report precision determinations of the beam-normal single spin asymmetries (A_{n}) in the elastic scattering of 0.95 and 2.18 GeV electrons off ^{12}C, ^{40}Ca, ^{48}Ca, and ^{208}Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of A_{n} for ^{40}Ca and ^{48}Ca are found to be similar to that of ^{12}C, consistent with expectations and thus demonstrating the validity of theoretical calculations for nuclei with Z≤20. We also report A_{n} for ^{208}Pb at two new momentum transfers (Q^{2}) extending the previous measurement. Our new data confirm the surprising result previously reported, with all three data points showing significant disagreement with the results from the Z≤20 nuclei. These data confirm our basic understanding of the underlying dynamics that govern A_{n} for nuclei containing ≲50 nucleons, but point to the need for further investigation to understand the unusual A_{n} behavior discovered for scattering off ^{208}Pb.

8.
Faraday Discuss ; 236(0): 389-411, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35543123

RESUMEN

Valence electronic structure is crucial for understanding and predicting reactivity. Valence non-resonant X-ray photoelectron spectroscopy (NRXPS) provides a direct method for probing the overall valence electronic structure. However, it is often difficult to separate the varying contributions to NRXPS; for example, contributions of solutes in solvents or functional groups in complex molecules. In this work we show that valence resonant X-ray photoelectron spectroscopy (RXPS) is a vital tool for obtaining atomic contributions to valence states. We combine RXPS with NRXPS and density functional theory calculations to demonstrate the validity of using RXPS to identify atomic contributions for a range of solutes (both neutral and ionic) and solvents (both molecular solvents and ionic liquids). Furthermore, the one-electron picture of RXPS holds for all of the closed shell molecules/ions studied, although the situation for an open-shell metal complex is more complicated. The factors needed to obtain a strong RXPS signal are investigated in order to predict the types of systems RXPS will work best for; a balance of element electronegativity and bonding type is found to be important. Additionally, the dependence of RXPS spectra on both varying solvation environment and varying local-covalent bonding is probed. We find that RXPS is a promising fingerprint method for identifying species in solution, due to the spectral shape having a strong dependence on local-covalency but a weak dependence on the solvation environment.

9.
Phys Rev Lett ; 126(17): 172502, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988387

RESUMEN

We report a precision measurement of the parity-violating asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{208}Pb. We measure A_{PV}=550±16(stat)±8(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(Q^{2}=0.00616 GeV^{2})=0.368±0.013. Combined with our previous measurement, the extracted neutron skin thickness is R_{n}-R_{p}=0.283±0.071 fm. The result also yields the first significant direct measurement of the interior weak density of ^{208}Pb: ρ_{W}^{0}=-0.0796±0.0036(exp)±0.0013(theo) fm^{-3} leading to the interior baryon density ρ_{b}^{0}=0.1480±0.0036(exp)±0.0013(theo) fm^{-3}. The measurement accurately constrains the density dependence of the symmetry energy of nuclear matter near saturation density, with implications for the size and composition of neutron stars.

10.
Nature ; 524(7566): 442-5, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-26310764

RESUMEN

Electrical breakdown sets a limit on the kinetic energy that particles in a conventional radio-frequency accelerator can reach. New accelerator concepts must be developed to achieve higher energies and to make future particle colliders more compact and affordable. The plasma wakefield accelerator (PWFA) embodies one such concept, in which the electric field of a plasma wake excited by a bunch of charged particles (such as electrons) is used to accelerate a trailing bunch of particles. To apply plasma acceleration to electron-positron colliders, it is imperative that both the electrons and their antimatter counterpart, the positrons, are efficiently accelerated at high fields using plasmas. Although substantial progress has recently been reported on high-field, high-efficiency acceleration of electrons in a PWFA powered by an electron bunch, such an electron-driven wake is unsuitable for the acceleration and focusing of a positron bunch. Here we demonstrate a new regime of PWFAs where particles in the front of a single positron bunch transfer their energy to a substantial number of those in the rear of the same bunch by exciting a wakefield in the plasma. In the process, the accelerating field is altered--'self-loaded'--so that about a billion positrons gain five gigaelectronvolts of energy with a narrow energy spread over a distance of just 1.3 metres. They extract about 30 per cent of the wake's energy and form a spectrally distinct bunch with a root-mean-square energy spread as low as 1.8 per cent. This ability to transfer energy efficiently from the front to the rear within a single positron bunch makes the PWFA scheme very attractive as an energy booster to an electron-positron collider.

11.
Clin Radiol ; 76(5): 333-341, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33461746

RESUMEN

AIM: To establish the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) and compare its performance to that of international criteria from European Assofor the Study of the Liver (EASL), Japan Society of Hepatology (JSH), Asian Pacific Association for the Study of the Liver (APASL), and Organ Procurement and Transplantation Network (OPTN), and to the reporting radiologist's overall opinion regarding the probability of a nodule being a HCC by correlating with a histological diagnosis from whole liver explants. MATERIALS AND METHODS: The present single-centre, retrospective review selected participants based on the following criteria: adults (≥18 years) listed for liver transplantation in 2014/2015, with liver cirrhosis at the time of magnetic resonance imaging (MRI) with hepatocyte specific contrast agent, and at least one liver lesion ≥10 mm on MRI with histology from subsequent liver explant for comparison. Each lesion was assessed against international criteria and given a "radiologist opinion" score of 1-5 (1 = definitely benign, 5 = definitely HCC). RESULTS: Total 268 patient records were reviewed, with 105 eligible lesions identified from 47 patients. Median lesion size was 15.5 mm (range 10-68 mm). Sensitivity (%), specificity (%), and positive predictive value (PPV; %) for LI-RADS LR5 was 45, 89, and 89, for LI-RADS LR4+5 + TIV was 61, 80, and 86, for EASL was 44, 86 and 86, for JSH/APASL was 64, 81, and 87, for OPTN was 36, 90, and 88, and for "radiologist impression" of probably or definitely HCC was 79, 79, and 88 respectively. CONCLUSIONS: MRI has moderate sensitivity and good specificity for the diagnosis of HCC with considerable variation depending on criteria used. OPTN criteria have the best specificity, but low sensitivity. "Radiologist opinion" gives highest overall accuracy with increases in sensitivity and reduction in specificity when compared to the imaging criteria.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Gadolinio DTPA , Aumento de la Imagen/métodos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sistemas de Información Radiológica , Adulto , Anciano , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Medios de Contraste , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
12.
Nature ; 515(7525): 92-5, 2014 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25373678

RESUMEN

High-efficiency acceleration of charged particle beams at high gradients of energy gain per unit length is necessary to achieve an affordable and compact high-energy collider. The plasma wakefield accelerator is one concept being developed for this purpose. In plasma wakefield acceleration, a charge-density wake with high accelerating fields is driven by the passage of an ultra-relativistic bunch of charged particles (the drive bunch) through a plasma. If a second bunch of relativistic electrons (the trailing bunch) with sufficient charge follows in the wake of the drive bunch at an appropriate distance, it can be efficiently accelerated to high energy. Previous experiments using just a single 42-gigaelectronvolt drive bunch have accelerated electrons with a continuous energy spectrum and a maximum energy of up to 85 gigaelectronvolts from the tail of the same bunch in less than a metre of plasma. However, the total charge of these accelerated electrons was insufficient to extract a substantial amount of energy from the wake. Here we report high-efficiency acceleration of a discrete trailing bunch of electrons that contains sufficient charge to extract a substantial amount of energy from the high-gradient, nonlinear plasma wakefield accelerator. Specifically, we show the acceleration of about 74 picocoulombs of charge contained in the core of the trailing bunch in an accelerating gradient of about 4.4 gigavolts per metre. These core particles gain about 1.6 gigaelectronvolts of energy per particle, with a final energy spread as low as 0.7 per cent (2.0 per cent on average), and an energy-transfer efficiency from the wake to the bunch that can exceed 30 per cent (17.7 per cent on average). This acceleration of a distinct bunch of electrons containing a substantial charge and having a small energy spread with both a high accelerating gradient and a high energy-transfer efficiency represents a milestone in the development of plasma wakefield acceleration into a compact and affordable accelerator technology.

13.
Tech Coloproctol ; 24(6): 563-571, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32232594

RESUMEN

BACKGROUND: Prescription of opioid medication after ambulatory anorectal surgery may be excessive and lead to opioid misuse. The purpose of this study was to evaluate the efficacy of a multi-modality opioid-sparing approach to control postoperative pain and reduce opioid prescriptions after outpatient anorectal surgery. METHODS: A prospective non-inferiority pre- and post-intervention study was completed at three academic hospitals. Patients included were 18-75 years of age who had outpatient anorectal surgeries. The Standardization of Outpatient Procedure (STOP) Narcotics intervention was implemented, which is a multi-pronged analgesia bundle integrating patient education, health care provider education, and intra-/postoperative analgesia focused on multi-modal pain control strategies and opioid-reduced prescriptions. The primary outcome was patient-reported average pain in the first 7 postoperative days. Secondary outcomes included patient-reported quality of pain management, medication utilization, prescription refills and medication disposal. RESULTS: Ninety-three patients had outpatient anorectal surgery (42 pre-intervention and 51 post-intervention). No difference was seen in average postoperative pain in the pre- vs. post-intervention groups (2.8 vs. 2.6 on an 11-point scale, p = 0.33) or patient-reported quality of pain control (good/very good in 57% vs. 63%, p = 0.58). The median oral morphine equivalents (OME) prescribed was significantly less [112.5 (IQR 50-150) pre-intervention vs. 50 (IQR 50-50) post-intervention, p < 0.001]. In the post-intervention group, only 45% of patients filled their opioid prescription and median opioid use was 12.5 OME (2.5 pills). CONCLUSIONS: While pain control after anorectal surgery must consider the individual patient's needs, a standardized pain care bundle significantly decreased opioid prescribing without an increase in patient-reported postoperative pain.


Asunto(s)
Analgésicos Opioides , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Humanos , Narcóticos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Pacientes Ambulatorios , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Pautas de la Práctica en Medicina , Estudios Prospectivos , Estándares de Referencia
14.
J Mammary Gland Biol Neoplasia ; 24(3): 257-270, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31104199

RESUMEN

Germline mutations in the breast cancer susceptibility gene BRCA1, encoding a tumor suppressor protein, greatly enhance the risk of breast and ovarian cancer. This tissue-specificity implicates the role of ovarian hormones. Indeed, BRCA1 has been demonstrated to regulate the signalling axis of the hormone, progesterone, and its receptor, the progesterone receptor (PR), and progesterone action has been implicated in BRCA1-related tumorigenesis. BRCA1 also plays important roles in oxidative stress and activating nuclear factor kappaB (NFκB) signalling pathways. Like wildtype BRCA1 function, PR signalling has also been shown to inhibit NFκB activation. Although PR and BRCA1 networks are known to interact, their interaction at the level of NFκB activation in the human breast is not understood. This study investigates the effect of reduced BRCA1 expression on proliferation and NFκB activation in human breast cells, and the impact of progesterone on these effects. The major findings are that: 1) Reduced BRCA1 levels inhibit cell growth in normal human mammary cells and breast cancer cells; 2) Reduced BRCA1 levels stimulated inflammatory targets and NFκB activity in normal human mammary cells; 3) Wildtype BRCA1 inhibited the pro-proliferative effects of progesterone in normal mammary epithelial cells, and; 4) Progesterone attenuated BRCA1-mediated NFκB activation in normal human mammary cells. These data have important implications for our understanding of progesterone action in BRCA1 mutation carriers, and how inhibition of this action may potentially delay tumorigenesis or impart a more favourable prognosis.


Asunto(s)
Proteína BRCA1/metabolismo , Neoplasias de la Mama/patología , Mama/patología , Proliferación Celular , Células Epiteliales/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , FN-kappa B/metabolismo , Progesterona/farmacología , Proteína BRCA1/antagonistas & inhibidores , Proteína BRCA1/genética , Biomarcadores de Tumor/genética , Mama/efectos de los fármacos , Mama/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Transformación Celular Neoplásica , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Humanos , FN-kappa B/genética , Progestinas/farmacología , ARN Interferente Pequeño/genética , Transducción de Señal
15.
Phys Rev Lett ; 123(13): 134801, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31697514

RESUMEN

An intense, subpicosecond, relativistic electron beam traversing a dielectric-lined waveguide generates very large amplitude electric fields at terahertz (THz) frequencies through the wakefield mechanism. In recent work employing this technique to accelerate charged particles, the generation of high-power, narrow-band THz radiation was demonstrated. The radiated waves contain fields with measured amplitude exceeding 2 GV/m, orders of magnitude greater than those available by other THz generation techniques at a narrow bandwidth. For fields approaching the GV/m level, a strong damping has been observed in SiO_{2}. This wave attenuation with an onset near 850 MV/m is consistent with changes to the conductivity of the dielectric lining and is characterized by a distinctive latching mechanism that is reversible on longer timescales. We describe the detailed measurements that serve to clarify the underlying physical mechanisms leading to strong field-induced damping of THz radiation (hω=1.59 meV, f=0.38 THz) in SiO_{2}, a bulk, wide band-gap (8.9 eV) dielectric.

16.
Philos Trans A Math Phys Eng Sci ; 377(2151): 20180184, 2019 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-31230576

RESUMEN

This paper discusses the properties of electron beams formed in plasma wakefield accelerators through ionization injection. In particular, the potential for generating a beam composed of co-located multi-colour beamlets is demonstrated in the case where the ionization is initiated by the evolving charge field of the drive beam itself. The physics of the processes of ionization and injection are explored through OSIRIS simulations. Experimental evidence showing similar features are presented from the data obtained in the E217 experiment at the FACET facility of the SLAC National Laboratory. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

17.
J Hum Nutr Diet ; 32(6): 754-764, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31144413

RESUMEN

BACKGROUND: The present study assessed the relationship between night-time eating and body weight status among US adults, using in-person 24-h dietary recall data from a nationally representative survey. METHODS: Individual-level data (n = 23 003) came from the 2007-2016 National Health and Nutrition Examination Survey (NHANES) (five waves). Multivariate linear and logistic regressions were performed to estimate the effect of energy, sugar, fat and saturated fat intake during night-time on body mass index (BMI), obesity (BMI ≥30 kg m-2 ), waist circumference (WC) and abdominal obesity (WC ≥88 cm in women; WC ≥102 cm in men), adjusting for daily total energy intake, physical activity, sleeping and other individual characteristics. RESULTS: Approximately 36.5% and 56.7% of the NHANES adult participants had obesity and abdominal obesity, respectively. The proportion of energy, total fat, saturated fat and total sugar intake within the time window of 00.00 h to 05.59 h and 22.00 h to 23.59 h averaged 5.7%, 5.3%, 5.7% and 6.8%, respectively. Energy intake within the time window was not found to be associated with BMI, WC, obesity or abdominal obesity in the regression analyses. Sensitivity analyses applying alternative time windows to capture night-time eating found night-time intakes of energy, total fat, saturated fat and total sugar not to be associated BMI, WC, obesity or abdominal obesity. CONCLUSIONS: Night-time eating was not found to be associated with body weight status in a US nationally representative adult sample. Restricting night-time food consumption alone without an overall reduction in daily caloric intake may not prevent obesity. The findings of the present study warrant replication in a future experimental study with habitual dietary behaviour measures.


Asunto(s)
Peso Corporal , Conducta Alimentaria , Adolescente , Adulto , Anciano , Índice de Masa Corporal , Ritmo Circadiano , Grasas de la Dieta/administración & dosificación , Azúcares de la Dieta/administración & dosificación , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Obesidad/epidemiología , Obesidad Abdominal/epidemiología , Factores de Tiempo , Estados Unidos/epidemiología , Circunferencia de la Cintura
18.
Public Health ; 167: 70-77, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30639806

RESUMEN

OBJECTIVES: This study aims to assess adequacy in micronutrient intake in comparison with reference nutrient intakes (RNI) and to identify differences in intakes between normal weight and overweight individuals. STUDY DESIGN: A sample of 542 university students (18-25 years), normal weight (N = 369) and overweight (N = 173), were included in a cross-sectional study. METHODS: A three-day diet diary was used to assess energy and nutrient intake. Body mass index (BMI) and waist circumference were measured. RESULTS: Mean dietary vitamin D intake was lower than RNI in both men (4.44 µg) and women (5.04 µg). Mean intakes of calcium (597.44 mg), iron (8.62 mg) and folate (171.29 mg) were also lower than recommendations in women. Weight status (normal weight versus overweight) was significantly associated with micronutrient intake, and a trend towards a decrease in vitamin and mineral intake with increasing weight was noted. CONCLUSIONS: Results suggest the need to increase the intake of some micronutrients to meet the RNI, to ensure optimal health. This study provides a helpful tool to reinforce recommendations and potential health promotion and intervention strategies in university settings and could influence manufacturers involved in new food product development targeted to this young population.


Asunto(s)
Peso Corporal Ideal , Micronutrientes/administración & dosificación , Micronutrientes/deficiencia , Sobrepeso , Adolescente , Adulto , Estudios Transversales , Dieta/estadística & datos numéricos , Inglaterra , Femenino , Humanos , Masculino , Estado Nutricional , Estudiantes/estadística & datos numéricos , Universidades , Adulto Joven
19.
Rhinology ; 57(6): 420-429, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31490466

RESUMEN

BACKGROUND: The aim of this study was to analyse rates of antibiotic usage in chronic rhinosinusitis (CRS) in primary care in England and Wales and to identify trends in the choice of antibiotics prescribed. METHODS: We used linked data from primary care EHRs, with diagnoses coded using the Read terminology (Clinical Practice Research Datalink) from consenting general practices, with (2) hospital care administrative records (Hospital Episode Statistics, HES recorded using ICD-10). RESULTS: From the total of 88,317 cases of CRS identified, 40,462 (46%) had an antibiotic prescription within 5 days of their first CRS diagnosis. Of patients receiving a first line antibiotic within 5 days of CRS diagnosis, over 80%, in each CRS group, received a subsequent prescription for an antibiotic. Within 5 years of diagnosis, 9% are estimated to have had 5 or more antibiotics within 5 days of a CRS-related consultation. With data spanning almost 20 years, it was possible to discern trends in antibiotics prescriptions, with a clear increasing trend towards macrolide and tetracycline prescribing evident. CONCLUSIONS: While antibiotics may have been prescribed for acute exacerbations, we have found high rates of repeated antibiotic prescription in some patients with CRS in primary care. There is a need for stronger evidence on the role of antibiotics in CRS management.


Asunto(s)
Antibacterianos/uso terapéutico , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Enfermedad Crónica , Registros Electrónicos de Salud/estadística & datos numéricos , Inglaterra/epidemiología , Humanos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Rinitis/epidemiología , Sinusitis/epidemiología , Gales/epidemiología
20.
Rhinology ; 57(4): 252-260, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30928998

RESUMEN

BACKGROUND: Macrolide antibiotics have demonstrated important anti-inflammatory and immunomodulatory properties in chronic rhinosinusitis (CRS) patients. However, reports of increased risks of cardiovascular events have led to safety concerns. We investigated the risk of all-cause and cardiac death, and cardiovascular outcomes, associated with macrolide use. METHODOLOGY: Observational cohort (1997-2016) using linked data from the Clinical Practice Research Datalink, Hospital Episodes Statistics, and the Office for National Statistics. Patients aged 16-80 years with CRS prescribed a macrolide antibiotic or penicillin were included, comparing prescriptions for macrolide antibiotics to penicillin. Outcomes were all-cause mortality, cardiac death, myocardial infarction, stroke, diagnosis of peripheral vascular disease, and cardiac arrhythmia. RESULTS: Analysis included 320,798 prescriptions received by 66,331 patients. There were 3,251 deaths, 815 due to cardiovascular causes, 925 incident myocardial infarctions, 859 strokes, 637 diagnoses of peripheral vascular disease, and 1,436 cardiac arrhythmias. A non-statistically significant trend towards increased risk of myocardial infarction during the first 30 days following macrolide prescription was observed. No statistically significant short- or long-term risks were observed for macrolide prescription. No significant risks were identified for clarithromycin in particular. CONCLUSIONS: Although not statistically significant, our best estimates suggest an increased short-term risk of myocardial infarction in patients with CRS following macrolide prescription, supporting previous observational evidence. However, confounding by indication remains a possible explanation for this apparent increased risk. We found no evidence of longer term increased risks.


Asunto(s)
Antibacterianos , Enfermedades Cardiovasculares , Macrólidos , Rinitis , Sinusitis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Registros Electrónicos de Salud , Humanos , Macrólidos/efectos adversos , Macrólidos/uso terapéutico , Persona de Mediana Edad , Atención Primaria de Salud , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Adulto Joven
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