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1.
Phys Rev Lett ; 122(17): 173603, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31107076

RESUMEN

A strong optical nonlinearity arises when coherent light is scattered by a semiconductor quantum dot coupled to a nanophotonic waveguide. We exploit the Fano effect in such a waveguide to control the phase of the quantum interference underpinning the nonlinearity, experimentally demonstrating a tunable quantum optical filter which converts a coherent input state into either a bunched or an antibunched nonclassical output state. We show theoretically that the generation of nonclassical light is predicated on the formation of a two-photon bound state due to the interaction of the input coherent state with the quantum dot. Our model demonstrates that the tunable photon statistics arise from the dependence of the sign of two-photon interference (either constructive or destructive) on the detuning of the input relative to the Fano resonance.

2.
Opt Lett ; 43(9): 2142-2145, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714766

RESUMEN

We demonstrate electro-mechanical control of an on-chip GaAs optical beam splitter containing a quantum dot single-photon source. The beam splitter consists of two nanobeam waveguides, which form a directional coupler (DC). The splitting ratio of the DC is controlled by varying the out-of-plane separation of the two waveguides using electromechanical actuation. We reversibly tune the beam splitter between an initial state, with emission into both output arms, and a final state with photons emitted into a single output arm. The device represents a compact and scalable tuning approach for use in III-V semiconductor integrated quantum optical circuits.

3.
Bone Joint J ; 99-B(9): 1223-1231, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28860404

RESUMEN

AIMS: We reviewed all patients who sustained a fracture of the hip and were treated in Northern Ireland over a period of 15 years to identify trends in incidence, the demographics of the patients, the rates of mortality, the configuration of the fracture and the choice of implant. PATIENTS AND METHODS: Since 01 January 2001 data about every fracture of the hip sustained in an adult have been collected centrally in Northern Ireland. All adults with such a fracture between 2000 and 2015 were included in the study. Temporal changes in their demographics, the mode of treatment, and outcomes including mortality were analysed. RESULTS: The incidence of fractures of the hip, in Northern Ireland, rose from 54 in 100 000 in 2000 to 86 in 100 000 in 2015. If these trends continue, we predict this rising to 128 in 100 000 in 2030. We found that these patients are becoming older and increasingly frail, as assessed by the American Association of Anesthesiology grade. Complex extracapsular fractures have become more common since 2009, which may explain the increased use of cephalomedullary nails. Despite increasing frailty, the 30-day and 12-month rates of mortality fell significantly (p = 0.002 and 0.001, respectively). CONCLUSION: Fractures of the hip are becoming more common and more complex in an aging, increasingly frail population. We expect these trends to continue. This will place an increasing economic and clinical strain on healthcare systems. Forward planning is essential to put systems in place that can deal with the increasing demand. Cite this article: Bone Joint J 2017;99-B:1223-31.


Asunto(s)
Fracturas de Cadera/epidemiología , Fracturas Osteoporóticas/epidemiología , Anciano , Anciano de 80 o más Años , Femenino , Anciano Frágil , Fracturas de Cadera/mortalidad , Fracturas de Cadera/cirugía , Humanos , Incidencia , Masculino , Irlanda del Norte/epidemiología , Fracturas Osteoporóticas/mortalidad , Fracturas Osteoporóticas/cirugía
4.
Nano Lett ; 16(12): 7414-7420, 2016 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-27960503

RESUMEN

We investigate the nonlinear mechanical properties of GaAs nanowires with anisotropic cross-section. Fundamental and second order flexural modes are studied using laser interferometry with good agreement found between experiment and theory describing the nonlinear response under mechanical excitation. In particular, we demonstrate that the sign of the nonlinear coupling between orthogonal modes is dependent on the cross-section aspect ratio. The findings are of interest for applications such as amplitude to frequency conversion and vectorial force sensing.

5.
Vet J ; 200(1): 51-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24721312

RESUMEN

Sample submissions to the Animal Health and Veterinary Laboratories Agency's (AHVLA's) diagnostic laboratory network in England and Wales were reviewed for diseases affecting New World camelids (NWCs). In the years 2000-2011, 6757 submissions were analysed, including 5154/6757 (76.3%) for diagnosing a disease problem and 1603/6757 (23.7%) for monitoring (no clinical disease). Wasting (weight loss, ill-thrift) was the most commonly reported clinical sign across all age groups. A diagnosis was reached for 1765/5154 (34.2%) diagnostic submissions. The proportion of submissions with diagnoses was higher for carcasses than non-carcass samples and multiple diagnoses were more likely to be reached from carcasses. Parasitic diseases were collectively the most common problem, including parasitic gastroenteritis (319/1765, 18.2%), coccidiosis (187/1765, 10.6%), fascioliasis (151/1765, 8.6%), ectoparasitic infestations (86/1765, 4.9%) and cryptosporidiosis (24/1765, 1.4%). The most frequently diagnosed non-parasitic problems included nutritional diseases (182/1765, 10.3%), septicaemia (104/1765, 5.9%, including 45 cases of colisepticaemia), gastric ulceration (79/1765, 4.5%), tumours/neoplastic diseases (65/1765, 3.7%), tuberculosis (57/1765, 3.2%), clostridial diseases (44/1765, 2.5%), congenital anomalies (41/1765, 2.3%), peritonitis (39/1765, 2.2%) and Johne's disease (20/1765, 1.1%).


Asunto(s)
Crianza de Animales Domésticos , Camélidos del Nuevo Mundo , Enfermedades Transmisibles/veterinaria , Animales , Animales Domésticos , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/etiología , Inglaterra/epidemiología , Estudios Retrospectivos , Gales/epidemiología
7.
Nano Lett ; 13(3): 861-5, 2013 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-23398085

RESUMEN

The potential for scale-up coupled with minimized system size is likely to be a major determining factor in the realization of applicable quantum information systems. Nanofabrication technology utilizing the III-V semiconductor system provides a path to scalable quantum bit (qubit) integration and a materials platform with combined electronic/photonic functionality. Here, we address the key requirement of qubit-site and emission energy control for scale-up by demonstrating uniform arrays of III-V nanowires, where each nanowire contains a single quantum dot. Optical studies of single nanowire quantum dots reveal narrow linewidth exciton and biexciton emission and clear state-filling at higher powers. Individual nanowire quantum dots are shown to emit nonclassically with clear evidence of photon antibunching. A model is developed to explain unexpectedly large excited state separations as revealed by photoluminescence emission spectra. From measurements of more than 40 nanowire quantum dots, we find emission energies with an ensemble broadening of 15 meV. The combination of deterministic site control and the narrow distribution in ensemble emission energy results in a system readily capable of scaling for multiqubit quantum information applications.

8.
Vet J ; 195(1): 80-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22850354

RESUMEN

Bronchodilators are frequently used to attenuate airway obstruction in equine heaves (or recurrent airway obstruction). This study evaluated the selective (M(3) and M(1)) muscarinic antagonist revatropate, which offers potential advantages over non-specific antimuscarinic agents such as ipratropium. Protocol 1 assessed the response to inhaled revatropate (1, 2 and 7 mg) using a blinded, negative (inhaled saline) and positive (inhaled ipratropium bromide; 0.3, 0.7 and 2mg) controlled, dose escalation study, with six heaves horses. The lowest doses of revatropate and ipratropium induced a rapid (within 1h) and significant improvement in airway function. The highest doses of both drugs had no significant effect on gastrointestinal sound score or iris function, but resulted in tacky mucous membranes and reduced gastrointestinal sound score in some horses. In Protocol 2, a cross-over design comparing the duration of action of inhaled revatropate (1mg), ipratropium (0.3mg) and saline, some indices of airway function were improved for between 5 and 6h after revatropate administration, and for between 6 and 24h after ipratropium administration. Inhaled revatropate and ipratropium had similar effects on airway function, with no significant difference between their efficacies. Importantly, however, only revatropate significantly improved clinical scores of breathing effort, improving combined clinical score at the 1h time point and abdominal score at the 1-3h time points. No significant adverse events were observed in Protocol 2, although some horses had reduced gastrointestinal sound scores. Inhaled revatropate is therefore a safe and effective bronchodilator for treating airway obstruction in heaves.


Asunto(s)
Broncodilatadores/uso terapéutico , Enfermedades de los Caballos/tratamiento farmacológico , Enfermedades Pulmonares Obstructivas/veterinaria , Antagonistas Muscarínicos/uso terapéutico , Quinuclidinas/uso terapéutico , Animales , Broncodilatadores/efectos adversos , Estudios Cruzados , Caballos , Ipratropio/efectos adversos , Ipratropio/farmacología , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Antagonistas Muscarínicos/efectos adversos , Quinuclidinas/efectos adversos
10.
Vet Parasitol ; 190(1-2): 95-103, 2012 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-22763348

RESUMEN

Taeniid tapeworms which include Echinococcus and Taenia spp. are obligatory parasites of mammals with pathogenicity usually related to the larval stages of the life cycle. Two species (or genotypes) of Echinococcus, E. granulosus sensu stricto and E. equinus, as well as several Taenia spp. are endemic in the UK. Here we report on the occurrence of larval cystic stages of Echinococcus and Taenia spp. in captive mammals in the UK. Using molecular techniques we have identified E. granulosus (G1 genotype) in a guenon monkey and a Philippine spotted deer; E. equinus in a zebra and a lemur; E. ortleppi in a Philippine spotted deer; E. multilocularis in a macaque monkey and Taenia polyacantha in jumping rats. To the best of our knowledge this is the first report of E. multilocularis in a captive primate translocated to the UK. As far as we know these are the first reports of E. equinus in a primate (lemur) and in a zebra; as well as E. granulosus (G1 genotype) and E. ortleppi in a cervid translocated to the UK. These infections and implications of the potential establishment of exotic species of cestodes are discussed.


Asunto(s)
Animales de Zoológico/parasitología , Equinococosis/veterinaria , Echinococcus/aislamiento & purificación , Mamíferos/parasitología , Taenia/aislamiento & purificación , Teniasis/veterinaria , Animales , Secuencia de Bases , Cercopithecus/parasitología , ADN de Helmintos/genética , Ciervos/parasitología , Equinococosis/epidemiología , Equinococosis/parasitología , Equinococosis/patología , Echinococcus/genética , Equidae/parasitología , Femenino , Genotipo , Lemuridae/parasitología , Hígado/parasitología , Hígado/patología , Pulmón/parasitología , Pulmón/patología , Macaca/parasitología , Masculino , Datos de Secuencia Molecular , Enfermedades de los Primates/epidemiología , Enfermedades de los Primates/parasitología , Enfermedades de los Primates/patología , Roedores , Análisis de Secuencia de ADN , Taenia/genética , Teniasis/epidemiología , Teniasis/parasitología , Teniasis/patología , Reino Unido/epidemiología
11.
Vet Rec ; 170(14): 359, 2012 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-22427386

RESUMEN

The clinical signs, treatments used and spread of psoroptic mange in cattle from October 2007 until March 2011 are described. The disease was first diagnosed in South West Wales, having not been reported in Great Britain since the 1980s. The likely source was identified as a farm that had imported two animals from mainland Europe in the summer of 2006. Since that time, disease has been diagnosed on a further 22 premises, the majority in South West Wales but also in South East and Mid Wales and on one farm in England. Bought in animals harbouring the Psoroptes species mite but not showing clinical signs were considered the greatest risk of introducing the infestation into a herd. This, together with the difficulties of treatment to eliminate the parasite, means that it is unlikely that this outbreak has been controlled. There is also a continuing threat of importing the disease from abroad. The disease is not notifiable in the UK.


Asunto(s)
Enfermedades de los Bovinos/patología , Escabiosis/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/transmisión , Comercio , Notificación de Enfermedades , Brotes de Enfermedades/veterinaria , Inglaterra/epidemiología , Femenino , Masculino , Factores de Riesgo , Escabiosis/tratamiento farmacológico , Escabiosis/patología , Escabiosis/transmisión , Gales/epidemiología
15.
J Comp Pathol ; 145(1): 103-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21306730

RESUMEN

A pericardial myxoid liposarcoma was diagnosed in a common eland (Taurotragus oryx) based on gross, microscopical and immunohistochemical findings. The pericardial and epicardial tissues were soft and uniformly thickened. Microscopically, the neoplastic mass consisted of stellate cells embedded in a myxoid matrix. These cells contained cytoplasmic vacuoles stained by oil red O. Immunohistochemical analysis showed the neoplastic cells to express vimentin and S-100.


Asunto(s)
Liposarcoma Mixoide/veterinaria , Pericardio/patología , Rumiantes , Animales , Femenino , Inmunohistoquímica , Liposarcoma Mixoide/metabolismo , Liposarcoma Mixoide/patología
17.
Vet Pathol ; 47(4): 760-3, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20348489

RESUMEN

An 18-month-old cross-bred goat was presented with generalized erythema and thinning of the hair coat, as well as localized moderate scaling. Histopathological evaluation of skin biopsies showed hyperplasia and marked disruption of the infundibular epithelium owing to a predominant infiltrate of macrophages with multinucleated histiocytic giant cells and some lymphocytes, plasma cells, and eosinophils. Examination of peripheral blood and skin by polymerase chain reaction gave positive results for ovine herpesvirus type 2 consistent with a diagnosis of malignant catarrhal fever.


Asunto(s)
Alopecia/veterinaria , Foliculitis/veterinaria , Enfermedades de las Cabras/patología , Herpes Simple/veterinaria , Simplexvirus/aislamiento & purificación , Alopecia/patología , Alopecia/virología , Animales , ADN Viral/química , ADN Viral/genética , Femenino , Foliculitis/patología , Foliculitis/virología , Enfermedades de las Cabras/virología , Cabras , Herpes Simple/patología , Herpes Simple/virología , Histocitoquímica/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Simplexvirus/genética
19.
J Comp Pathol ; 142(4): 336-40, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19909967

RESUMEN

Epidermolysis bullosa (EB) was diagnosed in eight calves from four farms in the United Kingdom on the basis of clinical, histological and ultrastructural findings. In three affected herds, pedigree Simmental bulls had been mated with Simmental-cross cows. In a fourth herd two Holstein-Friesian calves were affected. Lesions included multifocal erosion and ulceration of the hard and soft palates, tongue, nares and gingiva, with onychomadesis (dysungulation). There was alopecia, erosion and crusting of the coronets, pasterns, fetlocks, carpi, hocks, flanks and axillae. Histopathological findings included segmental separation of full thickness epidermis from the dermis, with formation of large clefts containing eosinophilic fluid, extravasated red blood cells and small numbers of neutrophils. Follicular and interfollicular areas of skin were affected, with clefts extending around hair follicles and sometimes involving whole follicles. Ultrastructurally, there was evidence of vacuolar change within basal keratinocytes, corresponding to areas of histological clefting. Preliminary genetic screening of the candidate keratin genes (bKRT5 and bKRT14) has excluded mutations of these as the cause of this condition.


Asunto(s)
Epidermólisis Ampollosa/patología , Epidermólisis Ampollosa/veterinaria , Piel/patología , Piel/ultraestructura , Alopecia/genética , Alopecia/patología , Animales , Bovinos , Epidermis/patología , Epidermólisis Ampollosa/genética , Femenino , Queratinocitos/patología , Queratinas/genética , Mutación , Enfermedades de la Uña/genética , Enfermedades de la Uña/patología , Linaje , Embarazo , Reino Unido
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