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1.
Phys Rev Lett ; 126(1): 010501, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33480763

RESUMEN

We report high-fidelity state readout of a trapped ion qubit using a trap-integrated photon detector. We determine the hyperfine qubit state of a single ^{9}Be^{+} ion held in a surface-electrode rf ion trap by counting state-dependent ion fluorescence photons with a superconducting nanowire single-photon detector fabricated into the trap structure. The average readout fidelity is 0.9991(1), with a mean readout duration of 46 µs, and is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping. Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.

3.
J Wound Care ; 25(1): 5-6, 8-11, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26762492

RESUMEN

OBJECTIVE: To investigate whether nursing/care home staff regard pressure ulceration as a safeguarding issue; and to explore reporting mechanisms for pressure ulcers (PUs) in nursing/care homes. METHOD: Within one clinical commissioning group, 65 staff members from 50 homes completed a questionnaire assessing their experiences of avoidable and unavoidable PUs, grading systems, and systems in place for referral to safeguarding teams. Understanding of safeguarding was assessed in depth by interviews with 11 staff members. RESULTS: Staff observed an average of 2.72 PUs in their workplaces over the previous 12 months, judging 45.6% to be avoidable. Only a minority of respondents reported knowledge of a grading system (mostly the EPUAP/NPUAP system). Most respondents would refer PUs to the safeguarding team: the existence of a grading system, or guidance, appeared to increase that likelihood. Safeguarding was considered a priority in most homes; interviewees were familiar with the term safeguarding, but some confusion over its meaning was apparent. Quality of written documentation and verbal communication received before residents returned from hospital was highlighted. However, respondents expressed concern over lack of information regarding skin integrity. Most staff had received education regarding ulcer prevention or wound management during training, but none reported post-registration training or formal education programmes; reliance was placed on advice of district nurses or tissue viability specialists. CONCLUSION: Staff within nursing/care homes understand the fundamentals of managing skin integrity and the importance of reporting skin damage; however, national education programmes are needed to develop knowledge and skills to promote patient health-related quality of life, and to reduce the health-care costs of pressure damage. Further research to investigate understanding, knowledge and skills of nursing/care home staff concerning pressure ulcer development and safeguarding will become increasingly necessary, as levels of the older population who may require assisted living continue to rise.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Casas de Salud , Personal de Enfermería/organización & administración , Úlcera por Presión/enfermería , Úlcera por Presión/prevención & control , Cuidados de la Piel/enfermería , Competencia Clínica , Enfermería Geriátrica/métodos , Hogares para Ancianos , Humanos , Evaluación en Enfermería/métodos , Investigación en Evaluación de Enfermería
4.
Contemp Clin Trials ; 37(2): 301-11, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24556343

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) represents a range of liver conditions from simple fatty liver to progressive end stage liver disease requiring liver transplantation. NAFLD is common in the population and in certain sub groups (e.g. type 2 diabetes) up to 70% of patients may be affected. NAFLD is not only a cause of end stage liver disease and hepatocellular carcinoma, but is also an independent risk factor for type 2 diabetes and cardiovascular disease. Consequently, effective treatments for NAFLD are urgently needed. OBJECTIVES: The WELCOME study is testing the hypothesis that treatment with high dose purified long chain omega-3 fatty acids will have a beneficial effect on a) liver fat percentage and b) two histologically validated algorithmically-derived biomarker scores for liver fibrosis. DESIGN: In a randomised double blind placebo controlled trial, 103 participants with NAFLD were randomised to 15-18months treatment with either 4g/day purified long chain omega-3 fatty acids (Omacor) or 4g/day olive oil as placebo. Erythrocyte percentage DHA and EPA enrichment (a validated proxy for hepatic enrichment) was determined by gas chromatography. Liver fat percentage was measured in three discrete liver zones by magnetic resonance spectroscopy (MRS). We also measured body fat distribution, physical activity and a range of cardiometabolic risk factors. METHODS: Recruitment started in January 2010 and ended in June 2011. We identified 178 potential participants, and randomised 103 participants who met the inclusion criteria. The WELCOME study was approved by the local ethics committee (REC: 08/H0502/165; www.clinicalTrials.gov registration number NCT00760513).


Asunto(s)
Suplementos Dietéticos , Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/uso terapéutico , Ácidos Grasos Omega-3/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Proyectos de Investigación , Adulto , Biomarcadores , Pesos y Medidas Corporales , Dieta , Método Doble Ciego , Combinación de Medicamentos , Ejercicio Físico , Pruebas de Función Cardíaca , Humanos , Hígado/fisiopatología , Cirrosis Hepática/fisiopatología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Aceite de Oliva , Aptitud Física , Aceites de Plantas , Factores de Riesgo
5.
BJOG ; 120 Suppl 2: 56-63, v, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23841879

RESUMEN

The International Fetal and Newborn Growth Consortium for the 21(st) Century (INTERGROWTH-21(st) ) is a large-scale, population-based, multicentre project involving health institutions from eight geographically diverse countries, which aims to assess fetal, newborn and preterm growth under optimal conditions. Given the multicentre nature of the project and the expected number of preterm births, it is vital that all centres follow the same standardised clinical care protocols to assess and manage preterm infants, so as to ensure maximum validity of the resulting standards as indicators of growth and nutrition with minimal confounding. Moreover, it is well known that evidence-based clinical practice guidelines can reduce the delivery of inappropriate care and support the introduction of new knowledge into clinical practice. The INTERGROWTH-21(st) Neonatal Group produced an operations manual, which reflects the consensus reached by members of the group regarding standardised definitions of neonatal morbidities and the minimum standards of care to be provided by all centres taking part in the project. The operational definitions and summary management protocols were developed by consensus through a Delphi process based on systematic reviews of relevant guidelines and management protocols by authoritative bodies. This paper describes the process of developing the Basic Neonatal Care Manual, as well as the morbidity definitions and standardised neonatal care protocols applied across all the INTERGROWTH-21(st) participating centres. Finally, thoughts about implementation strategies are presented.


Asunto(s)
Cuidado del Lactante/normas , Enfermedades del Prematuro/terapia , Estudios Multicéntricos como Asunto/normas , Guías de Práctica Clínica como Asunto/normas , Proyectos de Investigación/normas , Desarrollo Infantil , Protocolos Clínicos , Técnica Delphi , Femenino , Desarrollo Fetal , Estudios de Seguimiento , Gráficos de Crecimiento , Humanos , Cuidado del Lactante/métodos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/diagnóstico , Manuales como Asunto , Estudios Multicéntricos como Asunto/métodos , Atención Perinatal/métodos , Atención Perinatal/normas , Embarazo , Nacimiento Prematuro/prevención & control
6.
Phys Rev Lett ; 107(26): 262501, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22243152

RESUMEN

The (2)H(e,e'p)n cross section at a momentum transfer of 3.5 (GeV/c)(2) was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle θ(nq) and to extract missing momentum distributions for fixed values of θ(nq) up to 0.55 GeV/c. In the region of 35°≤θ(nq)≤45° recent calculations, which predict that final-state interactions are small, agree reasonably well with the experimental data. Therefore, these experimental reduced cross sections provide direct access to the high momentum component of the deuteron momentum distribution in exclusive deuteron electrodisintegration.

7.
Scott Med J ; 55(3): 15-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20795511

RESUMEN

Research networks were introduced in the UK to facilitate and improve clinical research and stroke was seen as a priority topic for local research network development. The Scottish Stroke Research Network (SSRN) is one of 11 stroke research networks in the UK. In this article we review the progress of the Scottish Stroke Research Network in the three years since inception. Between 2006-2009 the number of active hospital research sites has increased from 10 to 22 expanding to involve 20 stroke research nurses. There was a corresponding 58% increase in recruitment of participants into stroke studies, from 376 in 2006/07 to 594 in 2008/09. The majority (17/20) of our current studies are interventional. Data from one of these, the CLOTs trial (Clots in Legs Or sTocking after Stroke), demonstrates that the annual recruitment in Scotland increased from a median of 94 (range 6-122) patients per year in the six years before the SSRN, to 140 (135-158) patients per year after SSRN involvement. We currently screen about 50% of Scottish stroke patients and approximately 5% of Scottish stroke patients are participating in research studies that we support. The SSRN has made good progress in the first three years. Increasing the recruitment of screened patients remains a challenge.


Asunto(s)
Investigación sobre Servicios de Salud/organización & administración , Ensayos Clínicos Controlados Aleatorios como Asunto , Accidente Cerebrovascular/terapia , Humanos , Tamizaje Masivo , Selección de Paciente , Escocia , Accidente Cerebrovascular/diagnóstico
8.
Diabet Med ; 27(3): 282-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20536490

RESUMEN

OBJECTIVE: We aimed to quantify socio-economic and ethnic inequalities in diabetes retinal screening. METHODS: Data were analysed for the retinal screening programme for three South London boroughs for the 18-month period to February 2009. Sight-threatening diabetic retinopathy (STDR) was defined as the occurrence of diabetic maculopathy, severe non-proliferative or proliferative diabetic retinopathy. Odds ratios were adjusted for sex, age group, duration and type of diabetes, self-reported ethnicity and deprivation quintile by participant postal code. RESULTS: There were 76 351 records obtained but, after excluding duplicate and ineligible records, data were analysed for 59 495 records from 31 484 subjects. There were 7026 (22%) subjects called for appointments who were not screened in the period, with 24 458 (78%) having one or more screening episodes. Non-attendance for screening was highest in young adults aged 18-34 years (32%) and in those aged 85 years or greater (28%). In the most deprived quintile, non-attendance was 23% compared with 21% in the least deprived quintile [odds ratio (OR) 1.37, 95% confidence interval (CI) 1.16-1.61, P < 0.001]. There were 2819 (11.5%) participants with STDR, including 10.8% in the least deprived quintile and 12.2% in the most deprived quintile (OR 1.10, 95% CI 0.95-1.16, P = 0.196). Compared with white Europeans (9.4%), STDR was higher in Africans (15.2%) and African Caribbeans (14.7%), resulting from a higher frequency of diabetic maculopathy. CONCLUSION: Socio-economic inequality in diabetes retinal screening may be smaller than reported in earlier studies. This study suggested an increased frequency of diabetic maculopathy among participants of African origins.


Asunto(s)
Retinopatía Diabética/diagnóstico , Retinopatía Diabética/etnología , Tamizaje Masivo/estadística & datos numéricos , Aceptación de la Atención de Salud , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Retinopatía Diabética/epidemiología , Femenino , Humanos , Londres/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Aceptación de la Atención de Salud/etnología , Carencia Psicosocial , Factores Socioeconómicos , Adulto Joven
9.
Rev Sci Instrum ; 81(3): 033507, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20383905

RESUMEN

We discuss the circuit design of a digital multiradian phase detector that measures the phase difference between two 10 kHz square wave TTL signals and provides the result as a binary number. The phase resolution of the circuit is 1/64 period and its dynamic range is 256 periods. This circuit has been developed for fusion plasma interferometry with submillimeter waves on the ASDEX Upgrade tokamak. The results from interferometric density measurement are discussed and compared to those obtained with the previously used phase detectors, especially with respect to the occurrence of phase jumps. It is illustrated that the new phase measurement provides a powerful tool for automatic real-time validation of the measured density, which is important for feedback algorithms that are sensitive to spurious density signals.

10.
Neuroscience ; 167(4): 1239-48, 2010 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-20211699

RESUMEN

This study examined whether regular exercise training, at a level that would be recommended for middle-aged people interested in improving fitness could lead to improved cognitive performance and increased blood flow to the brain in another primate species. Adult female cynomolgus monkeys were trained to run on treadmills for 1 h a day, 5 days a week, for a 5 month period (n=16; 1.9+/-0.4 miles/day). A sedentary control group sat daily on immobile treadmills (n=8). Half of the runners had an additional sedentary period for 3 months at the end of the exercise period (n=8). In all groups, half of the monkeys were middle-aged (10-12 years old) and half were more mature (15-17 years old). Starting the fifth week of exercise training, monkeys underwent cognitive testing using the Wisconsin General Testing Apparatus (WGTA). Regardless of age, the exercising group learned to use the WGTA significantly faster (4.6+/-3.4 days) compared to controls (8.3+/-4.8 days; P=0.05). At the end of 5 months of running monkeys showed increased fitness, and the vascular volume fraction in the motor cortex in mature adult running monkeys was increased significantly compared to controls (P=0.029). However, increased vascular volume did not remain apparent after a 3-month sedentary period. These findings indicate that the level of exercise associated with improved fitness in middle-aged humans is sufficient to increase both the rate of learning and blood flow to the cerebral cortex, at least during the period of regular exercise.


Asunto(s)
Cognición , Aprendizaje , Corteza Motora/irrigación sanguínea , Condicionamiento Físico Animal , Factores de Edad , Animales , Femenino , Macaca fascicularis
11.
Phys Rev Lett ; 101(18): 182502, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999823

RESUMEN

We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_{1} of the neutron and 3He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c);{2}. Global duality is observed for the spin-structure function g_{1} down to at least Q;{2}=1.8 (GeV/c);{2} in both targets. We have also formed the photon-nucleon asymmetry A1 in the resonance region for 3He and found no strong Q2 dependence above 2.2 (GeV/c);{2}.

12.
J Neurophysiol ; 99(6): 3136-43, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18337372

RESUMEN

With a nervous system of only 302 neurons, the free-living nematode Caenorhabditis elegans is a powerful experimental organism for neurobiology. However, the laboratory substrate commonly used in C. elegans research, a planar agarose surface, fails to reflect the complexity of this organism's natural environment, complicates stimulus delivery, and is incompatible with high-resolution optophysiology experiments. Here we present a new class of microfluidic devices for C. elegans neurobiology and behavior: agarose-free, micron-scale chambers and channels that allow the animals to crawl as they would on agarose. One such device mimics a moist soil matrix and facilitates rapid delivery of fluid-borne stimuli. A second device consists of sinusoidal channels that can be used to regulate the waveform and trajectory of crawling worms. Both devices are thin and transparent, rendering them compatible with high-resolution microscope objectives for neuronal imaging and optical recording. Together, the new devices are likely to accelerate studies of the neuronal basis of behavior in C. elegans.


Asunto(s)
Artefactos , Conducta Animal/fisiología , Caenorhabditis elegans/fisiología , Técnicas Analíticas Microfluídicas/métodos , Neurobiología , Animales , Actividad Motora
13.
Phys Rev Lett ; 98(15): 152001, 2007 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-17501338

RESUMEN

Cross-section values for Compton scattering on the proton were measured at 25 kinematic settings over the range s=5-11 and -t=2-7 GeV2 with a statistical accuracy of a few percent. The scaling power for the s dependence of the cross section at fixed center-of-mass angle was found to be 8.0+/-0.2, strongly inconsistent with the prediction of perturbative QCD. The observed cross-section values are in fair agreement with the calculations using the handbag mechanism, in which the external photons couple to a single quark.

14.
Phys Rev Lett ; 98(18): 182302, 2007 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-17501566

RESUMEN

We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.

15.
Phys Rev Lett ; 99(24): 242501, 2007 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-18233443

RESUMEN

The present experiment exploits the interference between the deeply virtual Compton scattering (DVCS) and the Bethe-Heitler processes to extract the imaginary part of DVCS amplitudes on the neutron and on the deuteron from the helicity-dependent D(e,e'gamma)X cross section measured at Q2=1.9 GeV2 and xB=0.36. We extract a linear combination of generalized parton distributions (GPDs) particularly sensitive to E_{q}, the least constrained GPD. A model dependent constraint on the contribution of the up and down quarks to the nucleon spin is deduced.

17.
Phys Rev Lett ; 96(2): 022003, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-16486563

RESUMEN

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero.

18.
Rheumatology (Oxford) ; 45(2): 196-200, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16377731

RESUMEN

OBJECTIVES: It has been proposed that disruption of the internal proprioceptive representation, via incongruent sensory input, may underpin pathological pain states, but experimental evidence relies on conflicting visual input, which is not clinically relevant. We aimed to determine the symptomatic effect of incongruent proprioceptive input, imparted by vibration of the wrist tendons, which evokes the illusion of perpetual wrist flexion and disrupts cortical proprioceptive representation. METHODS: Twenty-nine healthy and naive volunteers reported symptoms during five conditions: control, active and passive wrist flexion, extensor carpi radialis tendon vibration to evoke illusion of perpetual wrist flexion, and ulnar styloid (sham) vibration. No advice was given about possible illusions. RESULTS: Twenty-one subjects reported the illusion of perpetual wrist flexion during tendon vibration. There was no effect of condition or of whether or not subjects reported an illusion on discomfort/pain (P>0.28). Peculiarity, swelling and foreignness were greater during tendon vibration than during the other conditions, and greater during tendon vibration in those who reported an illusion of wrist flexion than in those who did not (P<0.05 for all). Symptoms were reported by at least two subjects in each condition and four subjects reported systemic symptoms (e.g. nausea). CONCLUSIONS: In healthy volunteers, incongruent proprioceptive input does not cause discomfort or pain but does evoke feelings of peculiarity, swelling and foreignness in the limb.


Asunto(s)
Ilusiones/fisiología , Dolor/etiología , Propiocepción/fisiología , Femenino , Humanos , Masculino , Náusea/etiología , Dimensión del Dolor , Estimulación Física/métodos , Desempeño Psicomotor , Tendones/fisiología , Vibración , Articulación de la Muñeca/fisiología
19.
Phys Rev Lett ; 97(26): 262002, 2006 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-17280421

RESUMEN

We present the first measurements of the e[over -->]p-->epgamma cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q(2) dependence (from 1.5 to 2.3 GeV(2)) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q(2). The helicity-independent cross section is also measured at Q(2)=2.3 GeV(2). We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation.

20.
Phys Rev Lett ; 95(14): 142002, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-16241646

RESUMEN

We present the first measurement of the Q2 dependence of the neutron spin structure function g2(n) at five kinematic points covering 0.57 (GeV/c)2 < or = Q2 < or = 1.34 (GeV/c)2 at x approximately = 0.2. Though the naive quark-parton model predicts g2 = 0, nonzero values occur in more realistic models of the nucleon which include quark-gluon correlations, finite quark masses, or orbital angular momentum. When scattering from a noninteracting quark, g2(n) can be predicted using next-to-leading order fits to world data for g1(n). Deviations from this prediction provide an opportunity to examine QCD dynamics in nucleon structure. Our results show a positive deviation from this prediction at lower Q2, indicating that contributions such as quark-gluon interactions may be important. Precision data obtained for g1(n) are consistent with next-to-leading order fits to world data.

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