2,867 research outputs found
Nonlinear optical properties of an electromagnetically-induced-transparency medium interacting with two quantized fields
ManuscriptWe study linear and nonlinear optical properties of electromagnetically induced transparency (EIT) medium interacting with two quantized laser fields for adiabatic EIT case. We show that EIT medium exhibits normal dispersion. Kerr and higher order nonlinear refractive-index coefficients are also calculated in a completely analytical form. It is indicated that EIT medium exhibits giant resonantly enhanced nonlinearities. We discuss the response of the EIT medium to nonclassical light fields and find that the polarization vanishes when the probe laser is initially in a nonclassical state of no single-photon coherence
Insights into long noncoding RNAs of naked mole rat (Heterocephalus glaber) and their potential association with cancer resistance
Additional file 4: Table S3. Differential expressed lncRNAs identified in naked mole rat (Heterocephalus glaber) genome
Totally thoracoscopic closure of ventricular septal defect without a robotically assisted surgical system: A summary of 119 cases
ObjectivesTo summarize the clinical outcomes of totally thoracoscopic closure of a ventricular septal defect (VSD).MethodsTotally thoracoscopic VSD closure was performed in 119 patients (66 boys; mean age, 7.1 ± 3.6 years). An additional 35 patients undergoing open-chest VSD closure were selected as a control group. Using 3 port incisions in the right chest, pericardiotomy, bicaval occlusion, atriotomy, and VSD closure were performed by thoracoscopy without the aid of a robotically assisted surgical system.ResultsCardiopulmonary bypass and aortic crossclamp times were 42.2 ± 9.8 and 32.5 ± 7.3 minutes, respectively. There were no deaths but 1 patient required insertion of a permanent pacemaker as a result of postoperative atrioventricular conduction block. The length of stay in the intensive care unit (11.0 ± 2.6 vs 22.9 ± 4.9 hours, P < .01) or postoperative hospital stay (4.2 ± 1.1 vs 6.6 ± 2.1 days, P < .03) in the thoracoscopic group were shorter than in the control group. The percentage of patients who required postoperative opioid analgesics in the thoracoscopic group was lower than in the control group (31.9% vs 74.2%, P < .001). Rate of blood transfusion during the operation (17.6% vs 65.7%, P = .001) and the postoperative use of opioid analgesics (31.9% vs 74.3%, P = .003) in the thoracoscopic group was lower than in the control group. Transesophageal echocardiographic analysis 4.6 ± 2.3 months after the operation showed complete closure of the defect.ConclusionsTotally thoracoscopic closure of VSD through a 3-port entry was safe and effective
Perspective of monochromatic gamma-ray line detection with the High Energy cosmic-Radiation Detection (HERD) facility onboard China's Space Station
HERD is the High Energy cosmic-Radiation Detection instrument proposed to
operate onboard China's space station in the 2020s. It is designed to detect
energetic cosmic ray nuclei, leptons and photons with a high energy resolution
( for electrons and photons and for nuclei) and a large
geometry factor ( for electrons and diffuse photons and for nuclei). In this work we discuss the capability of HERD to detect
monochromatic -ray lines, based on simulations of the detector
performance. It is shown that HERD will be one of the most sensitive
instruments for monochromatic -ray searches at energies between
to a few hundred GeV. Above hundreds of GeV, Cherenkov telescopes will
be more sensitive due to their large effective area. As a specific example, we
show that a good portion of the parameter space of a supersymmetric dark matter
model can be probed with HERD.Comment: 9 pages, 7 figures, matches version published in Astropart.Phy
A Low Complexity 16 X 16 Butler Matrix Design Using Eight-Port Hybrids
Beamforming networks such as Butler Matrices are important for multibeam array antenna applications. The challenge for Butler Matrix design is that their complexity increases with the number of ports. In this paper, a novel approach of designing a 16 X 16 Butler Matrix with significant structure simplification is presented. The eight-port hybrids with no crossovers are used to simplify the network. To ensure the network has the same magnitude and phase responses as the standard one, the location and phase shifting value of each fixed phase shifter are derived from the -matrix of each hybrid. A Butler Matrix network operating from 9 GHz–11 GHz is designed to validate this concept. The compensated microstrip 3-dB/90° directional coupler, the phase shifter with a shunt open-and-short stub and the crossover with a resonating patch are used to reduce the transmission loss and enable broadband operation
The mid-IR Luminosity Function at z<0.3 from 5MUSES: Understanding the Star-formation/AGN Balance from a Spectroscopic View
We present rest-frame 15 and 24 um luminosity functions and the corresponding
star-forming luminosity functions at z<0.3 derived from the 5MUSES sample.
Spectroscopic redshifts have been obtained for ~98% of the objects and the
median redshift is ~0.12. The 5-35 um IRS spectra allow us to estimate
accurately the luminosities and build the luminosity functions. Using a
combination of starburst and quasar templates, we quantify the star-formation
and AGN contributions in the mid-IR SED. We then compute the star-formation
luminosity functions at 15 um and 24 um, and compare with the total 15 um and
24 um luminosity functions. When we remove the contribution of AGN, the bright
end of the luminosity function exhibits a strong decline, consistent with the
exponential cutoff of a Schechter function. Integrating the differential
luminosity function, we find that the fractional contribution by star formation
to the energy density is 58% at 15 um and 78% at 24 um, while it goes up to
~86% when we extrapolate our mid-IR results to the total IR luminosity density.
We confirm that the active galactic nuclei play more important roles
energetically at high luminosities. Finally, we compare our results with work
at z~0.7 and confirm that evolution on both luminosity and density is required
to explain the difference in the LFs at different redshifts.Comment: 31 pages, 12 figures, accepted for Ap
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