1,922 research outputs found
Compensación de acoplos en un array lineal de parches microstrip
In the design process of array antennas,
coupling is one of the most important elements to be counted. The real feeding radiated coefficients can be quite different from the theoretical ones because of this effect. In this paper, a compensation method is presented allowing matching each element from the array. All the parameters which are part of the coupling process are obtained through measurements. An application to linear patch array is presented as an example
Heritability of motor skills: Study with monozygotic and dizygotic twins
El objetivo del estudio fue evaluar el poder relativo de contribución
genética y ambiental de la variación de capacidades motoras en gemelos
monocigóticos y dicigóticos. Método: participado 88 sujetos divididos en 56
monocigóticos y 32 dicigóticos de ambos sexos. Para la evaluación de la
flexibilidad fue realizado el test de flexión de cadera; para la potencia de
miembros inferiores fue aplicado el test contra movimiento y para la velocidad de
desplazamiento, el test de carrera de 30m. Para determinar el índice de
heredabilidad, utilizamos la ecuación: (h²) = (S²DZ–S²MZ)/S²DZx100. Fue
utilizado tratamiento descriptivo y el test Shapiro-Wilk. Con la varianza de datos
fueron calculados valores de tendencia central. Los datos fueron categorizados
en percentiles de 25%. Resultados: flexibilidad 16%, velocidad de
desplazamiento 83% y potencia de los miembros inferiores 70%.Conclusión:
Fue evidenciado mayor heredabilidad para las variables de potencia y velocidad,
y mayor influencia ambiental para la flexibilidadThe aim of the study was to assess the relative power of genetic and
environmental contributions to the variation of motor skills in monozygotic and
dizygotic twins. Method: For this study, participated 88 people divided in 56
monozygotic and 32 dizygotic twins of both sexes. For the assessment the
flexibility, was performed hip flexion test, for assessment the lower limb power,
was applied the test against movement and the speed of movement, the 30m
running test. To determine the index of heritability, was used an equation: (h ²)
= (S ²MZ- S²DZ) / S²DZx100. For the statistic, was used the descriptive
treatment and Shapiro-Wilk test. The variance values were calculated, through
the tendency central values. Data were categorized into percentiles of 25%.
Results: Flexibility was 16% by heritability influence, speed of movement 83%
of influence and for the lower limbs power were 70%. Conclusion: In this study
was demonstrated higher heritability for the variables of lower limbs power and
the speed of movement, and for the flexibility, a greater influence was linked for
environmental factor
Estimación del modelo de acoplamiento en un array de parches mediante la medida del campo radiado
In the design process of array antennas, coupling is one of the most important elements to be counted. The real feeding radiated coefficients can be quite different from the theoretical ones because of this effect. In this paper, a compensation method is presented allowing matching each element from the array. All the parameters which are part of the coupling process are obtained through measurements, and the model to obtain those parameters is presented. An application to linear patch array is presented as an example
Caracterización preliminar de emisiones de gases de efecto invernadero (CH4 y CO2) procedentes de volcanes de fango del Golfo de Cádiz
Mud volcanism represents an important migration pathway for methane and other gases
from deeper reservoirs to the surface; however most submarine sources remain poor quantified.
During SUBVENT2 cruise, water column over several mud volcanoes were surveyed for gas seepage
characterization. Water samples of ROV Niskin and Rosette-CTD Niskin bottles were recovered above
the Bonjardim, El Cid, Las Negras, Mercator, Algacel, Mvseis, Madrid and Yuma mud volcanoes, and
at three newly discovered, mud volcano like structures, to quantify overall gases release fluxes from
seabed. CO2 and CH4 concentrations were measured by potentiometric titration and using a gas
chromatograph, respectively, in order to understand the relationship between physicochemical and
geological processes. Gases concentrations decreased from shallower to deeper mud volcanoes.
Values varied widely within 50 to 200 nM for CH4 and between 400 to 1500 μatm for fCO2.
Greenhouse gases variations were large influenced by water column depth, temperature, salinity
and possibly by anaerobic oxidation of methane (AOM). Our observations suggest that the emission
of methane and carbon dioxide from the mud volcanoes structures studied here may be relevant at
the present as a part of the carbon global cycle.Versión del edito
Near real-time surveillance of the SARS-CoV-2 epidemic with incomplete data
When responding to infectious disease outbreaks, rapid and accurate estimation of the epidemic trajectory is critical. However, two common data collection problems affect the reliability of the epidemiological data in real time: missing information on the time of first symptoms, and retrospective revision of historical information, including right censoring. Here, we propose an approach to construct epidemic curves in near real time that addresses these two challenges by 1) imputation of dates of symptom onset for reported cases using a dynamically-estimated "backward" reporting delay conditional distribution, and 2) adjustment for right censoring using the NobBS software package to nowcast cases by date of symptom onset. This process allows us to obtain an approximation of the time-varying reproduction number (Rt) in real time. We apply this approach to characterize the early SARS-CoV-2 outbreak in two Spanish regions between March and April 2020. We evaluate how these real-time estimates compare with more complete epidemiological data that became available later. We explore the impact of the different assumptions on the estimates, and compare our estimates with those obtained from commonly used surveillance approaches. Our framework can help improve accuracy, quantify uncertainty, and evaluate frequently unstated assumptions when recovering the epidemic curves from limited data obtained from public health systems in other locations.PMD was supported by the fellowship Ramón Areces Foundation. JAH was funded by the National Institute of General Medical Sciences, Award U54GM088558, and the National Institutes of Health Director’s Early Independence, Award DP5-OD028145. ML was supported by the Morris-Singer Fund and by a subcontract from the Carnegie Mellon University under an award from the US Centers for Disease Control and Prevention, Award U01IP001121). MS was supported by the National Institute Of General Medical Sciences, Award R01GM130668-02. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S
Measurement of the relative rate of prompt χc0, χc1 and χc2 production at √s=7TeV
Prompt production of charmonium χc0, χc1 and χc2 mesons is studied using proton-proton collisions at the LHC at a centre-of-mass energy of √s=7TeV. The χc mesons are identified through their decay to J/ψγ, with J/ψ→μ+mu− using photons that converted in the detector. A data sample, corresponding to an integrated luminosity of 1.0fb−1 collected by the LHCb detector, is used to measure the relative prompt production rate of χc1 and χc2 in the rapidity range 2.0<y<4.5 as a function of the J/ψ transverse momentum from 3 to 20 GeV/c. First evidence for χc0 meson production at a hadron collider is also presented
Study of DJ meson decays to D+π−, D0π+ and D∗+π− final states in pp collisions
A study of D+π−, D0π+ and D∗+π− final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV with the LHCb detector. The D1(2420)0 resonance is observed in the D∗+π− final state and the D∗2(2460) resonance is observed in the D+π−, D0π+ and D∗+π− final states. For both resonances, their properties and spin-parity assignments are obtained. In addition, two natural parity and two unnatural parity resonances are observed in the mass region between 2500 and 2800 MeV. Further structures in the region around 3000 MeV are observed in all the D∗+π−, D+π− and D0π+ final states
Study of B0(s)→K0Sh+h′− decays with first observation of B0s→K0SK±π∓ and B0s→K0Sπ+π−
A search for charmless three-body decays of B 0 and B0s mesons with a K0S meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B0(s)→K0Sh+h′− decay modes (h (′) = π, K), relative to the well measured B0→K0Sπ+π− decay, are obtained. First observation of the decay modes B0s→K0SK±π∓ and B0s→K0Sπ+π− and confirmation of the decay B0→K0SK±π∓ are reported. The following relative branching fraction measurements or limits are obtained B(B0→K0SK±π∓)B(B0→K0Sπ+π−)=0.128±0.017(stat.)±0.009(syst.), B(B0→K0SK+K−)B(B0→K0Sπ+π−)=0.385±0.031(stat.)±0.023(syst.), B(B0s→K0Sπ+π−)B(B0→K0Sπ+π−)=0.29±0.06(stat.)±0.03(syst.)±0.02(fs/fd), B(B0s→K0SK±π∓)B(B0→K0Sπ+π−)=1.48±0.12(stat.)±0.08(syst.)±0.12(fs/fd)B(B0s→K0SK+K−)B(B0→K0Sπ+π−)∈[0.004;0.068]at90%CL
Observation of the decay
The decay is observed for the first
time, using proton-proton collisions collected with the LHCb detector
corresponding to an integrated luminosity of 3fb. A signal yield of
decays is reported with a significance of 6.2 standard deviations.
The ratio of the branching fraction of \B_c \rightarrow J/\psi K^+ K^- \pi^+
decays to that of decays is measured to be
, where the first uncertainty is statistical and the
second is systematic.Comment: 18 pages, 2 figure
- …