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Due to their low phase noise at high carrier frequencies, photonic microwave oscillators are continuously expanding their application areas including digital signal processing, telecommunications, radio astronomy, and RADAR and LIDAR systems. Currently, the lowest noise photonic oscillators rely on traditional optical frequency combs with multiple stabilization loops that incorporate large vacuum components and complex optoelectronic configurations. Hence, the resulting systems are not only challenging to operate but also expensive to maintain. Here, we introduce a significantly simpler solution: a Photonically Referenced Extremely STable Oscillator (PRESTO). PRESTO requires only three key components: a femtosecond laser, a fiber delay element, and a pulse timing detector. The generated microwave at 10â GHz has phase noise levels of -125, -145, and <-160â dBc/Hz at 1, 10, and >100â kHz, respectively, with an integrated timing jitter of only 2â fs root mean square (RMS) over [100â Hz-1â MHz]. This approach offers a reliable solution for simplifying and downsizing photonic oscillators while delivering high performance.
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Human infection with Mycobacterium bovis is reported infrequently in the United Kingdom. Most cases involve previous consumption of unpasteurized milk. We report a rare occurrence of 2 incidents of cat-to-human transmission of M. bovis during a cluster of infection in cats.
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Mycobacterium bovis , Tuberculosis/epidemiología , Tuberculosis/transmisión , Zoonosis/epidemiología , Zoonosis/transmisión , Adolescente , Adulto , Animales , Gatos , Genoma Bacteriano , Genómica/métodos , Genotipo , Humanos , Mycobacterium bovis/clasificación , Mycobacterium bovis/genética , Filogenia , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Adulto Joven , Zoonosis/diagnóstico , Zoonosis/microbiologíaRESUMEN
In 2017, Public Health England South East Health Protection Team (HPT) were involved in the management of an outbreak of Mycobacterium bovis (the causative agent of bovine tuberculosis) in a pack of working foxhounds. This paper summarises the actions taken by the team in managing the public health aspects of the outbreak, and lessons learned to improve the management of future potential outbreaks. A literature search was conducted to identify relevant publications on M. bovis. Clinical notes from the Public Health England (PHE) health protection database were reviewed and key points extracted. Animal and public health stakeholders involved in the management of the situation provided further evidence through unstructured interviews and personal communications. The PHE South East team initially provided 'inform and advise' letters to human contacts whilst awaiting laboratory confirmation to identify the infectious agent. Once M. bovis had been confirmed in the hounds, an in-depth risk assessment was conducted, and contacts were stratified in to risk pools. Eleven out of 20 exposed persons with the greatest risk of exposure were recommended to attend TB screening and one tested positive, but had no evidence of active TB infection. The number of human contacts working with foxhound packs can be large and varied. HPTs should undertake a comprehensive risk assessment of all potential routes of exposure, involve all other relevant stakeholders from an early stage and undertake regular risk assessments. Current guidance should be revised to account for the unique risks to human health posed by exposure to infected working dogs.
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We present a fiber-coupled balanced optical cross-correlator using waveguides in periodically-poled KTiOPO(4) (PPKTP). The normalized conversion efficiency of the waveguide device is measured to be η(0) = 1.02% / [W · cm(2)], which agrees well with theory and simulation. This result represents an expected improvement of a factor of 20 over previous bulk-optic devices. The sensitivity of the cross-correlator is characterized and shown to be comparable to the free-space bulk-optic version, with the potential for significant performance enhancements in the future.
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This article considers the process of ethical review of research on human subjects at a very large multinational consumer products company. The commercial context of this research throws up unique challenges and opportunities that make the ethics of the process of oversight distinct from mainstream medical research. Reflection on the justification of governance processes sheds important, contrasting light on the ethics of governance of other forms and context of research.
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Comercio/ética , Revisión Ética , Ética en Investigación , Experimentación Humana/ética , Industria Manufacturera/ética , Políticas , Investigación , Investigación Biomédica/ética , Comités de Ética en Investigación , HumanosRESUMEN
The incidence of bovine tuberculosis (TB, caused by Mycobacterium bovis) in cattle has been associated with TB in badgers (Meles meles) in parts of England. The aim was to identify badger-associated M. bovis reservoirs in the Edge Area, between the High- and Low-Risk Areas for cattle TB. Data from badger TB surveys were sparse. Therefore, a definition for a local M. bovis reservoir potentially shared by cattle and badgers was developed using cattle TB surveillance data. The performance of the definition was estimated through Latent Class Analysis using badger TB survey data. Spatial units (25 km2 ) in the Edge Area were classified as having a reservoir if they had (i) at least one TB incident in at least three of the previous 7 years, (ii) at least one TB incident in a cattle herd confirmed by post-mortem tests as due to M. bovis infection and not attributable to cattle movements in the previous 2 years and (iii) more confirmed TB incidents than un-confirmed in the previous 2 years. Approximately 20% of the Edge Area was classified as having a local M. bovis reservoir using the cattle-based definition. Assuming 15% TB prevalence in Edge Area badgers, sensitivity for the local M. bovis reservoir definition varied from 25.7% [95% credible interval (CrI): 10.7%-85.1%] to 64.8% (95% CrI: 48.1%-88.0%). Specificity was 91.9% (CrI: 83.6%-97.4%). Over 90% of the local reservoir was in stable endemic TB areas identified through previous work and its spatial distribution was largely consistent with local veterinary knowledge. Uncertainty in the reservoir spatial distribution was explored through its recalculation in spatial units shifted in different directions. We recommend that the definition is re-evaluated as further data on badger infection with M. bovis become available.
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Enfermedades de los Bovinos , Mustelidae , Mycobacterium bovis , Tuberculosis Bovina , Animales , Bovinos , Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/veterinaria , Incidencia , Mustelidae/microbiología , Prevalencia , Tuberculosis Bovina/epidemiologíaRESUMEN
We demonstrate high-quality distribution of 1.3 microm polarization-entangled photons generated from a fiber-coupled periodically poled KTiOPO(4) waveguide over 200 m fiber-optic cables. Time-multiplexed measurements with a 19% efficient superconducting nanowire single-photon detector at the remote location show a detected flux of 5.8 pairs/s at a pump power of 25 microW and an average two-photon quantum-interference visibility of 97.7% without subtraction of accidentals.
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We demonstrate efficient generation of photon pairs at 1316 nm in a fiber-coupled type-II phase-matched Rb-indiffused waveguide in periodically poled KTiOPO(4). The integrated waveguide source has a pair production rate of 2 x 10(7)/s/mW in a 1.08-nm bandwidth, in good agreement with a theoretical model that takes into account the transversal momentum imparted on the phase matching function by the waveguide. We achieve a Hong-Ou-Mandel quantum-interference visibility of 98.2% after subtraction of accidental coincidences, representing the highest reported value for a waveguide-based photon-pair source.
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For the first time to our knowledge, continuous nonsegmented channel waveguides in periodically poled KTiOPO(4) with guided orthogonal polarizations are used to demonstrate type II background-free second harmonic generation in the telecom band with 1.6%/(W cm(2)) normalized conversion efficiency. This constitutes a 90-fold improvement in aggregate conversion efficiency over its free space counterpart. Simulations show that the guided wave device should enable the measurement of timing fluctuations of optical pulse trains at the attosecond level in an optical cross correlation scheme.
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BACKGROUND: Against a background of interest in rates of diabetes in schizophrenia and related psychoses and claims that data from historical periods demonstrate a link that antedates modern antipsychotics, we sought to establish the rate of diabetes in first onset psychosis and subsequent prevalence in historical and contemporary cohorts. METHODS: Analysis of two epidemiologically complete databases of individuals admitted for mental illness. 3170 individuals admitted to the North Wales Asylum between 1875-1924 and tracked over 18,486 patient years and 394 North West Wales first admissions for schizophrenia and related psychoses between 1994 and 2006 and tracked after treatment. RESULTS: The prevalence of Type 2 diabetes among patients with psychoses at time of first admission in both historical and contemporary samples was 0%. The incidence of diabetes remained 0% in the historical sample throughout 15 years of follow-up but rose in the contemporary sample after 3, 5 and 6 years of treatment with an incidence rate double the expected population rate so that the 15 year prevalence is likely to be over 8%. CONCLUSION: No association was found between diabetes and serious mental illness, but there may be an association between diabetes and treatment.
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Diabetes Mellitus/epidemiología , Diabetes Mellitus/historia , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/historia , Esquizofrenia/epidemiología , Esquizofrenia/historia , Adolescente , Adulto , Anciano , Áreas de Influencia de Salud , Niño , Estudios de Cohortes , Femenino , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Índice de Severidad de la Enfermedad , Gales/epidemiologíaRESUMEN
Mycobacterium bovis can cause tuberculosis (TB) in social mammals including lions, cattle and man, but canine infections are considered rare. In 2016/17 we investigated a M. bovis TB outbreak in a pack of approximately 180 Foxhounds within the bovine TB Edge Area of England. We employed a combination of immunological tests including an interferon gamma release assay (IGRA) and a serological assay (DPP VetTB, Chembio). Test-positive hounds were euthanased and subjected to post-mortem examination (PME). Overall 164 hounds were tested; 97 (59%) responded positively to at least one test. Eighty-five (52%) dogs responded to M. bovis antigens by IGRA while only 21 (12.9%) had detectable serological responses. At PME three hounds (3.1%) had visible lesions (VL) due to M. bovis infection, later confirmed by culture. Samples from 24 non-VL hounds were cultured and M. bovis infection was confirmed in a further three hounds (11%). This study is the first investigation and report of an outbreak of M. bovis TB in a canine species. We establish that, in principle, diagnostic tests used for identifying infected individuals of other species can effectively be used in the dog. Further work is urgently needed to establish the sensitivity and specificity of the testing approach used in this study for future clinical application.
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Brotes de Enfermedades/veterinaria , Enfermedades de los Perros/microbiología , Mycobacterium bovis/aislamiento & purificación , Tuberculosis/veterinaria , Animales , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/epidemiología , Perros , Inglaterra/epidemiología , Pruebas Inmunológicas/veterinaria , Ensayos de Liberación de Interferón gamma/veterinaria , Mycobacterium bovis/inmunología , Sensibilidad y Especificidad , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Tuberculosis/microbiologíaRESUMEN
We present a theoretical and experimental comparison of spontaneous parametric down-conversion in periodically poled waveguides and bulk KTP crystals. We measured a waveguide pair generation rate of 2.9.10(6) pairs/s per mWof pump in a 1-nm band: more than 50 times higher than the bulk crystal generation rate.
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Angioplastia Coronaria con Balón/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Infarto del Miocardio/terapia , Servicios Médicos de Urgencia/organización & administración , Hospitales , Humanos , Evaluación de Procesos, Atención de Salud , Factores de Tiempo , Reino Unido , Estados UnidosRESUMEN
The visual preferences of human infants for faces that varied in their attractiveness and in their symmetry about the midline were explored. The aim was to establish whether infants' visual preference for attractive faces may be mediated by the vertical symmetry of the face. Chimeric faces, made from photographs of attractive and unattractive female faces, were produced by computer graphics. Babies looked longer at normal and at chimeric attractive faces than at normal and at chimeric unattractive faces. There were no developmental differences between the younger and older infants: all preferred to look at the attractive faces. Infants as young as 4 months showed similarity with adults in the 'aesthetic perception' of attractiveness and this preference was not based on the vertical symmetry of the face.
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Conducta de Elección/fisiología , Estética/psicología , Cara , Reconocimiento Visual de Modelos/fisiología , Femenino , Fijación Ocular/fisiología , Humanos , Lactante , Juicio/fisiología , Masculino , Percepción SocialAsunto(s)
Otitis Media/tratamiento farmacológico , Acetaminofén/uso terapéutico , Enfermedad Aguda , Analgésicos no Narcóticos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Niño , Humanos , Ibuprofeno/uso terapéutico , Ventilación del Oído Medio , Otitis Media/prevención & controlAsunto(s)
Otitis Media/tratamiento farmacológico , Acetaminofén/uso terapéutico , Enfermedad Aguda , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Niño , Humanos , Ibuprofeno/uso terapéutico , Ventilación del Oído Medio , Otitis Media/prevención & controlAsunto(s)
Otitis Media/tratamiento farmacológico , Enfermedad Aguda , Adolescente , Analgésicos no Narcóticos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Niño , Preescolar , Humanos , Lactante , Ventilación del Oído Medio , Otitis Media/prevención & control , Recurrencia , Xilitol/uso terapéuticoAsunto(s)
Otitis Media/tratamiento farmacológico , Enfermedad Aguda , Adolescente , Analgésicos no Narcóticos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Niño , Preescolar , Humanos , Lactante , Ventilación del Oído Medio , Otitis Media/prevención & control , Recurrencia , Xilitol/uso terapéuticoRESUMEN
BACKGROUND: Venturia inaequalis is an economically-important disease of apple causing annual epidemics of scab worldwide. The pathogen is a heterothallic ascomycete with an annual cycle of sexual reproduction on infected apple leaf litter, followed by several cycles of asexual reproduction during the apple growing season. Current disease control is achieved mainly through scheduled applications of fungicides. Genetic linkage maps are essential for studying genome structure and organisation, and are a valuable tool for identifying the location of genes controlling important traits of interest such as avirulence, host specificity and mating type in V. inaequalis. In this study, we performed a wide cross under in vitro conditions between an isolate of V. inaequalis from China and one from the UK to obtain a genetically diverse mapping population of ascospore progeny isolates and produced a map using AFLP and microsatellite (SSR) markers. FINDINGS: Eighty-three progeny were obtained from the cross between isolates C0154 (China) x 01/213 (UK). The progeny was screened with 18 AFLP primer combinations and 31 SSRs, and scored for the mating type locus MAT. A linkage map was constructed consisting of 294 markers (283 AFLPs, ten SSRs and the MAT locus), spanning eleven linkage groups and with a total map length of 1106 cM. The length of individual linkage groups ranged from 30.4 cM (Vi-11) to 166 cM (Vi-1). The number of molecular markers per linkage group ranged from 7 on Vi-11 to 48 on Vi-3; the average distance between two loci within each group varied from 2.4 cM (Vi-4) to 7.5 cM (Vi-9). The maximum map length between two markers within a linkage group was 15.8 cM. The MAT locus was mapped to a small linkage group and was tightly linked to two AFLP markers. The map presented is over four times longer than the previously published map of V. inaequalis which had a total genetic distance of just 270 cM. CONCLUSION: A genetic linkage map is an important tool for investigating the genetics of important traits in V. inaequalis such as virulence factors, aggressiveness and mating type. The linkage map presented here represents a significant improvement over currently published maps for studying genome structure and organisation, and for mapping genes of economic importance on the V. inaequalis genome.