385 research outputs found
Análisis de la transmisión de tramas STM-N sobre un enlace de fibra óptica DWDM
En este trabajo se presenta un análisis del desempeño de la capa física de un enlace DWDM de 66 km de fibra óptica monomodo sobre la cual se implementa un sistema SDH para envío de módulos STM-1 a 155 Mbps. Se muestran los resultados de la simulación computacional en Optisystem 7.0 (Versión Evaluación) para analizar las características de un sistema DWDM a una velocidad de 2.5 Gbps equivalente al envío de módulos STM-16. Los resultados de diagramas de ojo y BER muestran que es posible la distinción entre bits cuando el ruido térmico en el detector es inferior a 1x10-19 W/Hz. Se analizan mediciones experimentales de Jitter y su correspondiente comparación con el valor normatizado por la ITU-T para módulos STM-1. Se propone el uso de más longitudes de onda para aprovechar al máximo la capacidad de transmisión de la fibra o la instalación de interfaces de mayor velocidad en los extremos del enlace para el incremento del ancho de banda disponible.In this work, we present an analysis of physical layer performance of a DWDM-link of 66 km of single-mode optical fiber on which is implemented a SDH system to send STM-1 at 155 Mbps. We show the computational simulation in Optisystem 7.0 (Evaluation Version) to analyze the DWDM system characteristic at 2.5 Gbps equivalent to a STM-16 frame. The results of the eye diagram and BER show that is possible to distinguish between bits when the detector thermal-noise is less than 1x10-19W/Hz. We analyze experimental measurements of jitter and its corresponding comparison with the value normalized by the ITU-T for a STM-1 frame. The use of more wavelengths is proposed to maximize the transmission capacity of fiber optics or installation of interfaces with high capacity for increasing the available bandwidth
Triplet Exciton Generation in Bulk-Heterojunction Solar Cells based on Endohedral Fullerenes
Organic bulk-heterojunctions (BHJ) and solar cells containing the trimetallic
nitride endohedral fullerene 1-[3-(2-ethyl)hexoxy
carbonyl]propyl-1-phenyl-Lu3N@C80 (Lu3N@C80-PCBEH) show an open circuit voltage
(VOC) 0.3 V higher than similar devices with [6,6]-phenyl-C[61]-butyric acid
methyl ester (PC61BM). To fully exploit the potential of this acceptor molecule
with respect to the power conversion efficiency (PCE) of solar cells, the short
circuit current (JSC) should be improved to become competitive with the state
of the art solar cells. Here, we address factors influencing the JSC in blends
containing the high voltage absorber Lu3N@C80-PCBEH in view of both
photogeneration but also transport and extraction of charge carriers. We apply
optical, charge carrier extraction, morphology, and spin-sensitive techniques.
In blends containing Lu3N@C80-PCBEH, we found 2 times weaker photoluminescence
quenching, remainders of interchain excitons, and, most remarkably, triplet
excitons formed on the polymer chain, which were absent in the reference
P3HT:PC61BM blends. We show that electron back transfer to the triplet state
along with the lower exciton dissociation yield due to intramolecular charge
transfer in Lu3N@C80-PCBEH are responsible for the reduced photocurrent
Different phenotypes of drug-induced anaphylaxis—Data from the European Anaphylaxis Registry
Background
Drugs are a frequent cause of severe anaphylactic reactions. Here, we analyze a large dataset on drug induced anaphylaxis regarding elicitors, risk factors, symptoms, and treatment.
Methods
Data from the European Anaphylaxis Registry (2007–2019) with 1815 reported cases of drug-induced anaphylaxis were studied accordingly.
Results
Drugs are the third most frequent cause of anaphylaxis reported in the Anaphylaxis Registry. Among the eliciting groups of drugs analgesics and antibiotics were far most often reported. Female and senior patients were more frequently affected, while the number of children with DIA was low. DIA patients had symptoms affecting the skin and mucous membranes (n = 1525, 84.02%), the respiratory (n = 1300, 71.63%), the cardiovascular (n = 1251, 68.93%) and the gastrointestinal system (n = 549, 30.25%). Drugs caused significant more severe reactions, occurred more often in medical facilities and led to increased hospitalization rates in comparison to food and insect venom induced anaphylaxis. Adrenaline was used more often in patients with DIA than in anaphylaxis due to other causes. Patients with skin symptoms received more antihistamines and corticosteroids in the acute treatment, while gastrointestinal symptoms led to less adrenaline use.
Conclusion
The study contributes to a better understanding of DIA, with a large number of cases from Europe supporting previous data, e.g., analgesics and antibiotics being the most frequent culprits for DIA. Female gender and higher age are relevant risk factors and despite clear recommendations, the emergency treatment of DIA is not administered according to the guidelines.Peer Reviewe
Epidemiología del trauma por quemaduras en la población atendida en un hospital infantil. manizales 2004-2005
Antecedentes. Las lesiones por quemaduras se han convertidoen un problema de salud pública, especialmente enpaíses en desarrollo.Objetivo. Identificar la epidemiología del trauma por quemadurasen la población que consultó al servicio de urgenciasdel Hospital Infantil “Rafael Henao Toro” de la ciudadde Manizales en el período comprendido entre el año 2004y 2005.Material y métodos. Se realizó un estudio descriptivoretrospectivo con base en la revisión de 439 historias clínicas,evaluando las variables de edad, género, seguridad social,procedencia, área geográfica, causa, profundidad, gravedad,extensión en porcentaje, área corporal comprometida,estancia hospitalaria y compañía.Resultados. Se encontró que la mayoría de las quemadurasocurrieron en pacientes de un año de edad (21,6%),predominó el género masculino (59%). La mayoría notenía seguridad social (52,2%). El 44,9 por ciento de lospacientes residía en la ciudad de Manizales. La principaletiología fueron los alimentos en 194 pacientes (44,2%)predominando el grado I de quemadura en un 78,1 porciento, con gravedad moderada en 314 pacientes (71,5%).La media de estancia hospitalaria fue 11,99 días.Conclusiones. Se determinó una mayor frecuencia de quemadurasen niños, menores de cinco años, causadas poralimentos, en miembro superior y de gravedad moderada
Predicting sepsis severity at first clinical presentation:The role of endotypes and mechanistic signatures
BACKGROUND: Inter-individual variability during sepsis limits appropriate triage of patients. Identifying, at first clinical presentation, gene expression signatures that predict subsequent severity will allow clinicians to identify the most at-risk groups of patients and enable appropriate antibiotic use. METHODS: Blood RNA-Seq and clinical data were collected from 348 patients in four emergency rooms (ER) and one intensive-care-unit (ICU), and 44 healthy controls. Gene expression profiles were analyzed using machine learning and data mining to identify clinically relevant gene signatures reflecting disease severity, organ dysfunction, mortality, and specific endotypes/mechanisms. FINDINGS: Gene expression signatures were obtained that predicted severity/organ dysfunction and mortality in both ER and ICU patients with accuracy/AUC of 77–80%. Network analysis revealed these signatures formed a coherent biological program, with specific but overlapping mechanisms/pathways. Given the heterogeneity of sepsis, we asked if patients could be assorted into discrete groups with distinct mechanisms (endotypes) and varying severity. Patients with early sepsis could be stratified into five distinct and novel mechanistic endotypes, named Neutrophilic-Suppressive/NPS, Inflammatory/INF, Innate-Host-Defense/IHD, Interferon/IFN, and Adaptive/ADA, each based on ∼200 unique gene expression differences, and distinct pathways/mechanisms (e.g., IL6/STAT3 in NPS). Endotypes had varying overall severity with two severe (NPS/INF) and one relatively benign (ADA) groupings, consistent with reanalysis of previous endotype studies. A 40 gene-classification tool (accuracy=96%) and several gene-pairs (accuracy=89–97%) accurately predicted endotype status in both ER and ICU validation cohorts. INTERPRETATION: The severity and endotype signatures indicate that distinct immune signatures precede the onset of severe sepsis and lethality, providing a method to triage early sepsis patients
Observation of resonances consistent with pentaquark states in decays
Observations of exotic structures in the channel, that we refer to
as pentaquark-charmonium states, in decays are
presented. The data sample corresponds to an integrated luminosity of 3/fb
acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude
analysis is performed on the three-body final-state that reproduces the
two-body mass and angular distributions. To obtain a satisfactory fit of the
structures seen in the mass spectrum, it is necessary to include two
Breit-Wigner amplitudes that each describe a resonant state. The significance
of each of these resonances is more than 9 standard deviations. One has a mass
of MeV and a width of MeV, while the second
is narrower, with a mass of MeV and a width of MeV. The preferred assignments are of opposite parity, with one
state having spin 3/2 and the other 5/2.Comment: 48 pages, 18 figures including the supplementary material, v2 after
referee's comments, now 19 figure
Quantum numbers of the state and orbital angular momentum in its decay
Angular correlations in decays, with , and , are used to measure
orbital angular momentum contributions and to determine the value of
the meson. The data correspond to an integrated luminosity of 3.0
fb of proton-proton collisions collected with the LHCb detector. This
determination, for the first time performed without assuming a value for the
orbital angular momentum, confirms the quantum numbers to be .
The is found to decay predominantly through S wave and an upper limit
of at C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure
Precise measurements of the properties of the B-1(5721)(0,+) and B-2*(5747)(0,+) states and observation of B-+,B-0 pi(-,+) mass structures
Invariant mass distributions of B+π− and B0π+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1 of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1(5721)0,+ and B2(5747)0,+ states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B+π− and B0π+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ (5840)0,+ and BJ (5960)0,+, whose masses and widths are obtained under different hypotheses for their quantum numbers
Ag85-focused T-cell immune response controls Mycobacterium avium chronic infection
CD4+ T cells are essential players for the control of mycobacterial infections. Several mycobacterial antigens have been identified for eliciting a relevant CD4+ T cell mediated-immune response, and numerous studies explored this issue in the context of Mycobacterium tuberculosis infection. Antigen 85 (Ag85), a highly conserved protein across Mycobacterium species, is secreted at the early phase of M. tuberculosis infection leading to the proliferation of Ag85-specific CD4+ T cells. However, in the context of Mycobacterium avium infection, little is known about the expression of this antigen and the elicited immune response. In the current work, we investigated if a T cell receptor (TCR) repertoire mostly, but not exclusively, directed at Ag85 is sufficient to mount a protective immune response against M. avium. We show that P25 mice, whose majority of T cells express a transgenic TCR specific for Ag85, control M. avium infection at the same level as wild type (WT) mice up to 20 weeks post-infection (wpi). During M. avium infection, Ag85 antigen is easily detected in the liver of 20 wpi mice by immunohistochemistry. In spite of the propensity of P25 CD4+ T cells to produce higher amounts of interferon-gamma (IFNγ) upon ex vivo stimulation, no differences in serum IFNγ levels are detected in P25 compared to WT mice, nor enhanced immunopathology is detected in P25 mice. These results indicate that a T cell response dominated by Ag85-specific T cells is appropriate to control M. avium infection with no signs of immunopathology.This work was developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). Fellowships from the Portuguese Foundation for Science and Technoloy (FCT) were attributed to BCR (SFRH/BD/80352/2011; QREN-POPH through the Fundo Social Europeu (FSE) and national funds from MEC] and to CN (SFRH/BPD/112001/2015; POPH through FSE and national funds from MCTES). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Universidad y sociedad. Extensión del conocimiento
Este libro hace un análisis de la educación y propone migrar de una institución educativa a una organización de extensión del conocimiento (Mejía, 2011) toma más fuerza cada día, ya que obtiene una participación más activa en su actuar, y no solo se circunscribe a mejorar la gestión de las áreas funcionales de mercadeo, docencia, investigación, extensión, financiera, tecnología y administración (Gutiérrez, 2011), también cuenta con una visión más sistémica para conseguir la felicidad social y de las personas que conforman la organización educativa
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