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1.
Sci Adv ; 6(41)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028523

RESUMO

Realizing a fully connected network of quantum processors requires the ability to distribute quantum entanglement. For distant processing nodes, this can be achieved by generating, routing, and capturing spatially entangled itinerant photons. In this work, we demonstrate the deterministic generation of such photons using superconducting transmon qubits that are directly coupled to a waveguide. In particular, we generate two-photon N00N states and show that the state and spatial entanglement of the emitted photons are tunable via the qubit frequencies. Using quadrature amplitude detection, we reconstruct the moments and correlations of the photonic modes and demonstrate state preparation fidelities of 84%. Our results provide a path toward realizing quantum communication and teleportation protocols using itinerant photons generated by quantum interference within a waveguide quantum electrodynamics architecture.

2.
Br J Anaesth ; 124(3): 261-270, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31864719

RESUMO

BACKGROUND: The Duke Activity Status Index (DASI) questionnaire might help incorporate self-reported functional capacity into preoperative risk assessment. Nonetheless, prognostically important thresholds in DASI scores remain unclear. We conducted a nested cohort analysis of the Measurement of Exercise Tolerance before Surgery (METS) study to characterise the association of preoperative DASI scores with postoperative death or complications. METHODS: The analysis included 1546 participants (≥40 yr of age) at an elevated cardiac risk who had inpatient noncardiac surgery. The primary outcome was 30-day death or myocardial injury. The secondary outcomes were 30-day death or myocardial infarction, in-hospital moderate-to-severe complications, and 1 yr death or new disability. Multivariable logistic regression modelling was used to characterise the adjusted association of preoperative DASI scores with outcomes. RESULTS: The DASI score had non-linear associations with outcomes. Self-reported functional capacity better than a DASI score of 34 was associated with reduced odds of 30-day death or myocardial injury (odds ratio: 0.97 per 1 point increase above 34; 95% confidence interval [CI]: 0.96-0.99) and 1 yr death or new disability (odds ratio: 0.96 per 1 point increase above 34; 95% CI: 0.92-0.99). Self-reported functional capacity worse than a DASI score of 34 was associated with increased odds of 30-day death or myocardial infarction (odds ratio: 1.05 per 1 point decrease below 34; 95% CI: 1.00-1.09), and moderate-to-severe complications (odds ratio: 1.03 per 1 point decrease below 34; 95% CI: 1.01-1.05). CONCLUSIONS: A DASI score of 34 represents a threshold for identifying patients at risk for myocardial injury, myocardial infarction, moderate-to-severe complications, and new disability.


Assuntos
Tolerância ao Exercício/fisiologia , Indicadores Básicos de Saúde , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Biomarcadores/sangue , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Complicações Pós-Operatórias/mortalidade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Autorrelato , Inquéritos e Questionários
3.
Anaesthesia ; 73(12): 1524-1530, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30284241

RESUMO

Cardiac events are a common cause of peri-operative morbidity. Cardiopulmonary exercise testing can objectively assess risk, but it does not quantify myocardial ischaemia. With appropriate dietary preparation to suppress basal myocardial glucose uptake, positron emission tomography with 18 F-fluorodeoxyglucose can identify post-ischaemic myocardium, providing an attractive complement to exercise testing. We aimed to investigate the feasibility of this diagnostic algorithm. Patients referred for cardiopulmonary exercise testing before major cancer surgery were prospectively recruited. Exercise testing and positron emission tomography imaging were performed after a high fat-low carbohydrate meal. Protocol feasibility (primary end-point) included compliance with pre-test diet instructions and the completion of tests. Stress myocardial perfusion imaging was performed if either exercise testing or positron emission tomography was equivocal or positive for ischaemia. We recorded cardiac complications for 30 postoperative days. We enrolled 26 participants, 20 of whom completed protocol. Twenty-one participants proceeded to surgery: myocardial injury or infarction was diagnosed in three participants, two of whom had positive or equivocal positron emission tomography but negative myocardial perfusion imaging. We have shown that pre-operative cardiac positron emission tomography after cardiopulmonary exercise testing is feasible; protocol deviations were minor and did not affect image quality. Our findings warrant further investigation to compare the diagnostic utility of cardiac positron emission tomography imaging with standard pre-operative stress tests.


Assuntos
Teste de Esforço/métodos , Coração/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios/métodos , Procedimentos Cirúrgicos Operatórios/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Circulação Coronária , Dieta com Restrição de Carboidratos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Projetos Piloto
4.
Br J Dermatol ; 178(5): e332-e341, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29672835

RESUMO

This is the report from the fifth meeting of the Harmonising Outcome Measures for Eczema initiative (HOME V). The meeting was held on 12-14 June 2017 in Nantes, France, with 81 participants. The main aims of the meeting were (i) to achieve consensus over the definition of the core domain of long-term control and how to measure it and (ii) to prioritize future areas of research for the measurement of the core domain of quality of life (QoL) in children. Moderated whole-group and small-group consensus discussions were informed by presentations of qualitative studies, systematic reviews and validation studies. Small-group allocations were performed a priori to ensure that each group included different stakeholders from a variety of geographical regions. Anonymous whole-group voting was carried out using handheld electronic voting pads according to predefined consensus rules. It was agreed by consensus that the long-term control domain should include signs, symptoms, quality of life and a patient global instrument. The group agreed that itch intensity should be measured when assessing long-term control of eczema in addition to the frequency of itch captured by the symptoms domain. There was no recommendation of an instrument for the core outcome domain of quality of life in children, but existing instruments were assessed for face validity and feasibility, and future work that will facilitate the recommendation of an instrument was agreed upon.


Assuntos
Dermatite Atópica/terapia , Qualidade de Vida , Criança , Ensaios Clínicos como Assunto , Consenso , Previsões , Humanos , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença
5.
Br J Dermatol ; 175(1): 69-79, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27436240

RESUMO

This article is a report of the fourth meeting of the Harmonising Outcome Measures for Eczema (HOME) initiative held in Malmö, Sweden on 23-24 April 2015 (HOME IV). The aim of the meeting was to achieve consensus over the preferred outcome instruments for measuring patient-reported symptoms and quality of life for the HOME core outcome set for atopic eczema (AE). Following presentations, which included data from systematic reviews, consensus discussions were held in a mixture of whole group and small group discussions. Small groups were allocated a priori to ensure representation of different stakeholders and countries. Decisions were voted on using electronic keypads. For the patient-reported symptoms, the group agreed by vote that itch, sleep loss, dryness, redness/inflamed skin and irritated skin were all considered essential aspects of AE symptoms. Many instruments for capturing patient-reported symptoms were discussed [including the Patient-Oriented SCOring Atopic Dermatitis index, Patient-Oriented Eczema Measure (POEM), Self-Administered Eczema Area and Severity Index, Itch Severity Scale, Atopic Dermatitis Quickscore and the Nottingham Eczema Severity Score] and, by consensus, POEM was selected as the preferred instrument to measure patient-reported symptoms. Further work is needed to determine the reliability and measurement error of POEM. Further work is also required to establish the importance of pain/soreness and the importance of collecting information regarding the intensity of symptoms in addition to their frequency. Much of the discussion on quality of life concerned the Dermatology Life Quality Index and Quality of Life Index for Atopic Dermatitis; however, consensus on a preferred instrument for measuring this domain could not be reached. In summary, POEM is recommended as the HOME core outcome instrument for measuring AE symptoms.


Assuntos
Dermatite Atópica/terapia , Lista de Checagem , Ensaios Clínicos como Assunto , Fármacos Dermatológicos/uso terapêutico , Saúde Global , Humanos , Assistência de Longa Duração , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Literatura de Revisão como Assunto , Resultado do Tratamento
6.
Colorectal Dis ; 16(8): 595-602, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24612292

RESUMO

There have been recent advances in genetic testing enabling accurate diagnosis of polyposis syndromes by identifying causative gene mutations, which is essential in the management of individuals with polyposis syndrome and predictive genetic testing of their extended families. There are some similarities in clinical presentation of various polyposis syndromes, which may pose a challenge to diagnosis. In this review, we discuss the clinical presentation of the main polyposis syndromes and the process of genetic testing, including the latest advancement and future of genetic testing. We aim to reiterate the importance of genetic testing in the management of polyposis syndromes, potential pitfalls associated with genetic testing and recommendations for healthcare professionals involved with the care of polyposis patients.


Assuntos
Testes Genéticos/métodos , Polipose Intestinal/genética , Predisposição Genética para Doença , Humanos , Mutação , Síndrome
8.
Phys Rev Lett ; 108(26): 267003, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23005009

RESUMO

We present angle-resolved photoemission spectroscopy of Eu(1-x)Gd(x)O through the ferromagnetic metal-insulator transition. In the ferromagnetic phase, we observe Fermi surface pockets at the Brillouin zone boundary, consistent with density functional theory, which predicts a half-metal. Upon warming into the paramagnetic state, our results reveal a strong momentum-dependent evolution of the electronic structure, where the metallic states at the zone boundary are replaced by pseudogapped states at the Brillouin zone center due to the absence of magnetic long-range order of the Eu 4f moments.

9.
Am J Ophthalmol ; 150(6): 894-904, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20920813

RESUMO

PURPOSE: To evaluate the long-term results of autologous submandibular gland transplantation in eyes with cicatrizing conjunctivitis and to determine biomechanical and biochemical features of the resulting salivary tear film. DESIGN: Prospective, observational case series. METHODS: Fifteen eyes with cicatrizing conjunctivitis with a viable autologous submandibular gland transplantation were compared with 10 eyes with cicatrizing conjunctivitis and a failed submandibular gland transplantation or no submandibular gland transplantation. Best-corrected visual acuity, frequency of tear substitute instillation, severity of dry eye discomfort, lid margin erythema, conjunctival hyperemia, corneal epithelial edema, tear film break-up time, Schirmer test results, and corneal fluorescein and conjunctival Rose Bengal staining were evaluated. In a subgroup central corneal thickness and sensitivity, corneal epithelial barrier function, conjunctival and lid margin flora, and conjunctival impression cytologic analysis results were evaluated. In 3 patients, preoperative and postoperative tear samples were analyzed for viscosity, surface tension, and presence of mucins. RESULTS: Submandibular gland autotransplantation resulted in long-term improvement of subjective, objective, and some ocular surface parameters. Salivary mucins were detectable in salivary tears after submandibular gland transplantation. The viscosity of salivary tears was more similar to normal saliva and the surface tension was intermediate between the 2 original secretions. CONCLUSIONS: Submandibular gland autotransplantation provides long-term relief from pain and reduces the need for frequent installation of lubricants.


Assuntos
Cicatriz/cirurgia , Conjuntivite/cirurgia , Síndromes do Olho Seco/cirurgia , Glândula Submandibular/transplante , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cicatriz/patologia , Conjuntivite/complicações , Conjuntivite/fisiopatologia , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/fisiopatologia , Feminino , Seguimentos , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucinas/metabolismo , Complicações Pós-Operatórias , Estudos Prospectivos , Tensão Superficial , Lágrimas/química , Lágrimas/metabolismo , Transplante Autólogo , Viscosidade , Acuidade Visual/fisiologia , Adulto Jovem
10.
Eur Respir J ; 36(3): 488-93, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20110401

RESUMO

The aim of this study was to ascertain the population prevalence of chronic obstructive pulmonary disease (COPD) in an area with past heavy industry and to establish the relative contributions of occupational and other risk factors. We investigated respiratory symptoms and the prevalence of spirometrically-defined COPD in a population-based study in North-East England (UK) between 2002 and 2004. Questionnaires were posted to 6,000 males and 6,000 females, 45-69 yrs of age, who were randomly selected from a primary care database (response rate 64%, n = 7,566). Spirometric measurements were performed on 845 randomly selected responders. We defined COPD by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) II criteria. The prevalence of respiratory symptoms was 55%. Symptoms were strongly associated with smoking, occupational exposures and hay fever. COPD was present in 10% of subjects. Its presence was significantly associated with occupational exposures, smoking and hay fever. COPD is common in North-East England. Respiratory effects of occupational exposures can be detected within the general population: there were clear associations between occupational exposures and respiratory symptoms. The association with COPD was more marked in females.


Assuntos
Doença Pulmonar Obstrutiva Crônica/epidemiologia , Idoso , Estudos Transversais , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Prevalência , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Pneumologia/métodos , Fatores Sexuais , Espirometria/métodos , Inquéritos e Questionários , População Urbana
11.
Phys Rev Lett ; 105(25): 257206, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21231624

RESUMO

Rare earth doping is the key strategy to increase the Curie temperature (T(C)) of the ferromagnetic semiconductor EuO. The interplay between doping and charge carrier density (n), and the limit of the T(C) increase, however, are yet to be understood. We report measurements of n and T(C) of Gd-doped EuO over a wide range of doping levels. The results show a direct correlation between n and T(C), with both exhibiting a maximum at high doping. On average, less than 35% of the dopants act as donors, raising the question about the limit to increasing T(C).

12.
Science ; 326(5955): 977-80, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19965507

RESUMO

Piezoelectric materials, which convert mechanical to electrical energy and vice versa, are typically characterized by the intimate coexistence of two phases across a morphotropic phase boundary. Electrically switching one to the other yields large electromechanical coupling coefficients. Driven by global environmental concerns, there is currently a strong push to discover practical lead-free piezoelectrics for device engineering. Using a combination of epitaxial growth techniques in conjunction with theoretical approaches, we show the formation of a morphotropic phase boundary through epitaxial constraint in lead-free piezoelectric bismuth ferrite (BiFeO3) films. Electric field-dependent studies show that a tetragonal-like phase can be reversibly converted into a rhombohedral-like phase, accompanied by measurable displacements of the surface, making this new lead-free system of interest for probe-based data storage and actuator applications.

16.
Biomaterials ; 25(20): 4977-86, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15109859

RESUMO

Biodegradable scaffolds serve a central role for tissue engineering scaffolds and guiding tissue regeneration. Some of these scaffolds, including apatites, display a significant effect upon cell adhesion and cell proliferation. The incorporation of scaffold technology with the developing embryonic stem (ES) cell field and the capacity of ES cells for self-renewal and differentiation are believed to hold enormous potential for applications in biomedical research and regenerative medicine. The purpose of this work was to determine the effect of hydroxyapatite (HAP) and fluoride substitutions of HAP upon ES cell growth and colonisation. Sintered hydroxyfluorapatite discs were found to support cellular proliferation and colonisation, and the ES cells displayed a tendency for differentiation on the apatite surface as determined by reductions in colony Oct4 immunoreactivity. Fluoride-containing HAPs were found to provide equivalent support to gelatin in terms of cell numbers, yet superior support for cellular colonisation when compared to HAP. This study indicates that fluoride substitutions of HAP may represent a viable strategy for the development of certain engineered tissue replacements and tissue regeneration systems using ES cells.


Assuntos
Materiais Biocompatíveis/química , Cristalização/métodos , Embrião de Mamíferos/citologia , Fluoretos/química , Temperatura Alta , Hidroxiapatitas/química , Células-Tronco/citologia , Engenharia Tecidual/métodos , Análise de Variância , Animais , Apatitas/química , Materiais Biocompatíveis/síntese química , Cálcio/química , Diferenciação Celular , Proliferação de Células , Hidroxiapatitas/síntese química , Íons , Teste de Materiais , Camundongos , Tamanho da Partícula , Transição de Fase , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Difração de Raios X
17.
Cochrane Database Syst Rev ; (3): CD002143, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11687016

RESUMO

BACKGROUND: Palliative radiotherapy (RT) to the chest is often used in patients with lung cancer, but RT regimens are more often based on tradition than research results. OBJECTIVES: To discover the most effective and least toxic regimens of palliative RT, and whether higher doses increase survival. SEARCH STRATEGY: Electronic databases, reference lists, handsearching of journals and conference proceedings, and discussion with experts were used to identify potentially eligible trials, published and unpublished. SELECTION CRITERIA: Randomised controlled clinical trials comparing different regimens of palliative RT in patients with non-small lung cancer. DATA COLLECTION AND ANALYSIS: Ten randomised trials were reviewed. There were important differences in the doses of RT investigated, the patient characteristics and the outcome measures. Because of this heterogeneity no meta-analysis was attempted. MAIN RESULTS: There is no strong evidence that any regimen gives greater palliation. Higher dose regimens give more acute toxicity. There is evidence for a modest increase in survival (6% at 1 year and 3% at 2 years) in patients with better performance status (PS) given higher dose RT. REVIEWER'S CONCLUSIONS: The majority of patients should be treated with short courses of palliative RT, of 1 or 2 fractions. Care should be taken with the dose to the spinal cord. The use of high dose palliative regimens should be considered for and discussed with selected patients with good PS. More research is needed into reducing the acute toxicity of large fraction regimens and into the role of radical compared to high dose palliative RT and more homogeneous studies are needed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Cuidados Paliativos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Humanos , Neoplasias Pulmonares/mortalidade , Dosagem Radioterapêutica , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Cochrane Database Syst Rev ; (2): CD002143, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11406035

RESUMO

BACKGROUND: Palliative radiotherapy (RT) to the chest is often used in patients with lung cancer, but RT regimens are more often based on tradition than research results. OBJECTIVES: To discover the most effective and least toxic regimens of palliative RT, and whether higher doses increase survival. SEARCH STRATEGY: Electronic databases, reference lists, handsearching of journals and conference proceedings, and discussion with experts were used to identify potentially eligible trials, published and unpublished. SELECTION CRITERIA: Randomised controlled clinical trials comparing different regimens of palliative RT in patients with non-small lung cancer. DATA COLLECTION AND ANALYSIS: Ten randomised trials were reviewed. There were important differences in the doses of RT investigated, the patient characteristics and the outcome measures. Because of this heterogeneity no meta-analysis was attempted. MAIN RESULTS: There is no strong evidence that any regimen gives greater palliation. Higher dose regimens give more acute toxicity. There is evidence for a modest increase in survival (6% at 1 year and 3% at 2 years) in patients with better performance status (PS) given higher dose RT. REVIEWER'S CONCLUSIONS: The majority of patients should be treated with short courses of palliative RT, of 1 or 2 fractions. Care should be taken with the dose to the spinal cord. The use of high dose palliative regimens should be considered for and discussed with selected patients with good PS. More research is needed into reducing the acute toxicity of large fraction regimens and into the role of radical compared to high dose palliative RT and more homogeneous studies are needed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Cuidados Paliativos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Humanos , Neoplasias Pulmonares/mortalidade , Dosagem Radioterapêutica , Ensaios Clínicos Controlados Aleatórios como Assunto
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