2,745 research outputs found

    On the Benefits of Glide Symmetries for Microwave Devices

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    The presence of glide symmetries in periodic structures can introduce beneficial modifications in their electromagnetic properties. The difference between glide and non-glide periodic structures is due to the distinctive coupling between their constituent sub-unit cells. In this paper, we describe the recent discov eries on the remarkable properties of glide-symmetric periodic structures, which include widened stopbands, reduced dispersion, as well as enhanced anisotropy and magnetic response. These properties are explained through canonical structures simulated with two methods: mode matching and multimode transfer-matrix analysis. We also review the recent use of these distinctive properties for solving technological problems in practical devices such as filters, gap waveguide components, low-leakage flanges, compressed lenses, low-reflected material transitions and leaky-wave antennas with applications in 5G terrestrial communication systems, millimetre-wave satellite systems and automated contactless measurement techniquesGobierno de España Salvador de Madariaga PRX19/00025Ministerio de Ciencia, Innovación y Universidades TEC2017-84724-

    Entangled-State Lithography: Tailoring any Pattern with a Single State

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    We demonstrate a systematic approach to Heisenberg-limited lithographic image formation using four-mode reciprocal binominal states. By controlling the exposure pattern with a simple bank of birefringent plates, any pixel pattern on a (N+1)×(N+1)(N+1) \times (N+1) grid, occupying a square with the side half a wavelength long, can be generated from a 2N2 N-photon state.Comment: 4 pages, 4 figure

    Noteworthy records of Myotis Kaup, 1829 species in northeastern Guatemala, including the first record of M. volans (H. Allen, 1866) (Chiroptera, Vespertilionidae) from the country

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    Myotis is the most diverse genus of bats in Central America, with 10 species currently reported for Guatemala. Here, we present the first record of M. volans (H. Allen, 1866), and third record of M. auriculus Baker & Stains, 1955 in Guatemala, both from the cloud forest of the highlands of Sierra de las Minas Biosphere Reserve. This new locality may serve as one of the southernmost habitats akin to North American ecosystems for these two species. Our record of M. volans increases the number of bats in Guatemala to 105. Our findings underscore the importance of further research to understand patterns of biodiversity in Guatemala and Central America

    A simple technique can reduce cardiopulmonary bypass use during lung transplantation

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    Cardiopulmonary bypass causes an inflammatory response and consumption of coagulation factors, increasing the risk of bleeding and neurological and renal complications. Its use during lung transplantation may be due to pulmonary hypertension or associated cardiac defects or just for better exposure of the pulmonary hilum. We describe a simple technique, or open pericardium retraction, to improve hilar exposure by lifting the heart by upward retraction of the pericardial sac. This technique permits lung transplantation without cardiopulmonary bypass when bypass use is recommended only for better exposure

    Identification of a cytokine network sustaining neutrophil and Th17 activation in untreated early rheumatoid arthritis

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    © 2010 Cascão et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by sustained synovitis. Recently, several studies have proposed neutrophils and Th17 cells as key players in the onset and perpetuation of this disease. The main goal of this work was to determine whether cytokines driving neutrophil and Th17 activation are dysregulated in very early rheumatoid arthritis patients with less than 6 weeks of disease duration and before treatment (VERA). Methods: Cytokines related to neutrophil and Th17 activation were quantified in the serum of VERA and established RA patients and compared with other very early arthritis (VEA) and healthy controls. Synovial fluid (SF) from RA and osteoarthritis (OA) patients was also analyzed. Results: VERA patients had increased serum levels of cytokines promoting Th17 polarization (IL-1b and IL-6), as well as IL-8 and Th17-derived cytokines (IL-17A and IL-22) known to induce neutrophil-mediated inflammation. In established RA this pattern is more evident within the SF. Early treatment with methotrexate or corticosteroids led to clinical improvement but without an impact on the cytokine pattern. Conclusions: VERA patients already display increased levels of cytokines related with Th17 polarization and neutrophil recruitment and activation, a dysregulation also found in SF of established RA. 0 Thus, our data suggest that a cytokine-milieu favoring Th17 and neutrophil activity is an early event in RA pathogenesis.This work was supported by a grant from Sociedade Portuguesa de Reumatologia/Schering-Plough 2005. RAM and RC were funded by Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/30247/2006 and SFRH/BD/40513/2007, respectively. MMS-C was funded by Marie Curie Intra-European Fellowship PERG-2008-239422 and a EULAR Young Investigator Award

    Tumores estromales gastrointestinales (GISTs): estudio histopatológico y molecular, con valor pronóstico de 50 casos

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    3 p.Los tumores del estroma gastrointestinal (GISTs) representan el 1-2% de las neoplasias digestivas, y su topografía más frecuente es el estómago (47%)1-3. Las células intersticiales de Cajal (CIC) o células marcapasos del tracto gastrointestinal están implicadas en la génesis de dichos tumores. Aunque la proteína CD117 se consideraba el marcador inmunohistoquímico de elección 4,5, recientemente la proteína DOG1 (discovered on GIST1) ha sido utilizado con un alto porcentaje de sensibilidad y especificidad 6-7. La presentación clínica más frecuente es la hemorragia digestiva, siendo la cirugía el tratamiento de elección. El descubrimiento del mesilato de imatinib, cambió el pronóstico de los pacientes con enfermedad irresecable. Objetivos: Determinar la topografía, anatomía patológica y presentación clínica. Destacar el rol del protooncogén CD117 en el diagnóstico de GISTs.www.revistamorfologia.com.arFil: Caballero, Gustavo Alejandro. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Universitario de maternidad y Obstetrica. Cátedra II de Patología; Argentina.Fil: Fonseca, Ismael Bernardo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Universitario de Maternidad y Neonatología. Cátedra de Patología; Argentina.Fil: Guerini, Julio César. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Universitario de Maternidad y Neonatología. Cátedra de Patología; Argentina.Fil: Spitale, Luis Santos. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Nacional de Clínicas. Cátedra de Anatomía Patológica; Argentina.Fil: Spitale, Luis Santos. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Universitario de Maternidad y Neonatología. Cátedra de Patología; Argentina.Fil: Tessi, G. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Hospital Universitario de Maternidad y Neonatología. Cátedra de Patología; Argentina.Patologí

    Search for very-high-energy gamma-ray emission from the microquasar Cygnus X-1 with the MAGIC telescopes

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    The microquasar Cygnus X-1 displays the two typical soft and hard X-ray states of a black hole transient. During the latter, Cygnus X-1 shows a one-sided relativistic radio-jet. Recent detection of the system in the high energy (HE; E greater than or similar to 60 MeV) gamma-ray range with FermiLAT associates this emission with the outflow. Former MAGIC observations revealed a hint of flaring activity in the very high-energy (VHE; E greater than or similar to 100 GeV) regime during this X-ray state. We analyse ~ to 97 h of Cygnus X-1 data taken with the MAGIC telescopes between July 2007 and October 2014. To shed light on the correlation between hard X-ray and VHE gamma rays as previously suggested, we study each main X-ray state separately. We perform an orbital phase-folded analysis to look for variability in the VHE band. Additionally, to place this variability behaviour in a multiwavelength context, we compare our results with Fermi-LAT, AGILE, Swift-BAT, MAXI, RXTE-ASM, AMI and RATAN-600 data. We do not detect Cygnus X-1 in the VHE regime. We establish upper limits for each X-ray state, assuming a power-law distribution with photon index Γ = 3.2. For steady emission in the hard and soft X-ray states, we set integral upper limits at 95 %per cent confidence level for energies above 200 GeV at 2.6 x 10⁻¹² photons cm⁻² s⁻¹ and 1.0 x 10⁻¹¹ photons cm⁻² s ⁻¹, respectively. We rule out steady VHE gamma-ray emission above this energy range, at the level of theMAGIC sensitivity, originating in the interaction between the relativistic jet and the surrounding medium, while the emission above this flux level produced inside the binary still remains a valid possibility

    Sub-wavelength lithography over extended areas

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    We demonstrate a systematic approach to sub-wavelength resolution lithographic image formation on films covering areas larger than a wavelength squared. For example, it is possible to make a lithographic pattern with a feature size resolution of λ/[2(N+1)]\lambda/[2(N+1)] by using a particular 2M2 M-photon, multi-mode entangled state, where N<MN < M, and banks of birefringent plates. By preparing a statistically mixed such a state one can form any pixel pattern on a (N+1)2MN×(N+1)2MN(N+1) 2^{M-N} \times (N+1) 2^{M-N} pixel grid occupying a square with a side of L=2MN1L=2^{M-N-1} wavelengths. Hence, there is a trade-off between the exposed area, the minimum lithographic feature size resolution, and the number of photons used for the exposure. We also show that the proposed method will work even under non-ideal conditions, albeit with somewhat poorer performance.Comment: 8 pages, 8 figures, 1 table. Written in RevTe

    Oxazole Dyes With Potential For Photoluminescence Bioprobes: A Two-Photon Absorption Study

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    In this work, six π-conjugated oxazole compounds dissolved in dichloromethane were characterized with linear and nonlinear optical measurements. Z-scan with femtosecond laser pulses was employed to determine the two-photon absorption (TPA) spectra. Other photophysical parameters, such as absorbance, solvatochromism, lifetime fluorescence, and fluorescence anisotropy, were evaluated with linear optical techniques. The experimental TPA cross section spectra were adjusted by the sum-over-states (SOS) model, by which important parameters such as transition dipole moments and broadening parameters were determined. To better understand the TPA spectra of the oxazole compounds, quantum-chemical calculations using the response function formalism and the density functional theory level of theory were performed. Using the results provided by the quantum-chemical calculations and the broadening parameters estimated through the application of the SOS model, the TPA spectra were simulated by the superposition (summation) of individual homogeneous Lorentzian absorption profiles

    PATOGENICIDAD Y VIRULENCIA DE CEPAS DE BACILLUS THURINGIENSIS NATIVAS DEL ESTADO DE MORELOS SOBRE DIATRAEA MAGNIFACTELLA (LEPIDOPTERA: CRAMBIDAE)

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    Sugarcane is one of the most important industrial crops in Mexico, several insects feed on it, causing important economic losses. At the state of Morelos two species are found; Diatraea magnifactella and Eoreuma loftini. To control these borers chemical insecticides are used, today there are not any bioinsecticide based on entomopathogenic bacteria. It has already been reported in the literature against other borer species the use of entomopathogenic bacteria, so in this work was proposed to isolate Bacillus thuringiensis (Bt) from cadavers of D. magnifactella to evaluate the pathogenicity and virulence of bacterial isolates on neonate larva. It was possible the establishment a colony of D. magnifactella at laboratory, ensuring the health of the larvae used in bioassays. We obtained a total of 118 bacterial isolates, presumably from B. thuringiensis. Which were grouped into three groups, depending on thier protein profile. Six of the 118 strains caused more than 50% of mortality in neonate larvae of D. magnifactella. The LC50 of isolates been defined, the best was the B148 by 254.01 ng/cm2 of food. The LC50 the commercial strain HD1 was 417.61 ng/cm2, used as appositive control. The five remaining isolates showed LC50 greater than that of the positive control.La caña de azúcar representa uno de los cultivos industriales más importantes en México, diversos insectos se alimentan de ésta, provocando pérdidas económicas considerables. Para el estado de Morelos se reporta la presencia de los barrenadores Diatraea magnifactella y Eoreuma loftini. Para su control se han usado insecticidas químicos, a la fecha no existen bioinsecticidas a base de bacterias entomopatógenas. Existen reportes de evaluaciones in vitro y en campo contra otras especies de barrenadores, por lo que en el presente trabajo se aislaron cepas de Bacillus thuringiensis (Bt) a partir de cadáveres de D. magnifactella. Se evaluó la patogenicidad y virulencia de las cepas bacterianas sobre larvas neonatas del barrenador para lo cual se estableció un pie de cría de D. magnifactella en laboratorio, garantizando así la sanidad de las larvas usadas en los bioensayos. Se obtuvo un total de 118 cepas de B. thuringiensis. Los cuales se agruparon en tres categorías, dependiendo del peso molecular de las proteínas mayoritarias (perfil proteico) producidas por la bacteria. De los bioensayos de patogenicidad realizados, seis de las 118 cepas evaluadas fueron las que ocasionaron una mortalidad mayor al 50% en las larvas neonatas de D. magnifactella. Se determinó la Concentración Letal 50 de éstas seis cepas, la que presentó mejores resultados fue la cepa B148 con CL50 de 254.01 ng/cm2 de dieta, menor a la de la cepa comercial HD1 417.61 ng/cm2, evaluada como testigo positivo. Las cinco cepas restantes presentaron CL50 superiores a la de la cepa testigo
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