1,347 research outputs found
Realization of Zero-Refractive-Index Lens with Ultralow Spherical Aberration
Optical complex materials offer unprecedented opportunity to engineer
fundamental band dispersion which enables novel optoelectronic functionality
and devices. Exploration of photonic Dirac cone at the center of momentum space
has inspired an exceptional characteristic of zero-index, which is similar to
zero effective mass in fermionic Dirac systems. Such all-dielectric zero-index
photonic crystals provide an in-plane mechanism such that the energy of the
propagating waves can be well confined along the chip direction. A
straightforward example is to achieve the anomalous focusing effect without
longitudinal spherical aberration, when the size of zero-index lens is large
enough. Here, we designed and fabricated a prototype of zero-refractive-index
lens by comprising large-area silicon nanopillar array with plane-concave
profile. Near-zero refractive index was quantitatively measured near 1.55 um
through anomalous focusing effect, predictable by effective medium theory. The
zero-index lens was also demonstrated to perform ultralow longitudinal
spherical aberration. Such IC compatible device provides a new route to
integrate all-silicon zero-index materials into optical communication, sensing,
and modulation, and to study fundamental physics on the emergent fields of
topological photonics and valley photonics.Comment: 14 pages, 4 figure
Global analysis of measured and unmeasured hadronic two-body weak decays of antitriplet charmed baryons
A large amount of data on hadronic two body weak decays of anti-triplet
charmed baryons to an octet baryon and an octet or singlet
pseudoscalar meson , , have been measured. The SU(3)
flavor symmetry has been applied to study these decays to obtain insights about
weak interactions for charm physics. However not all such decays needed to
determine the SU(3) irreducible amplitudes have been measured forbidding a
complete global analysis. Previously, it has been shown that data from measured
decays can be used to do a global fit to determine all except one parity
violating and one parity conserving amplitudes of the relevant SU(3)
irreducible amplitudes causing 8 hadronic two body weak decay channels
involving to or transitions undetermined. It is
important to obtain information about these decays in order to guide
experimental searches. In this work using newly measured decay modes by BESIII
and Belle in 2022, we carry out a global analysis and parameterize the unknown
amplitudes to provide the ranges for the branching ratios of the 8 undetermined
decays. Our results indicate that the SU(3) flavor symmetry can explain the
measured data exceptionally well, with a remarkable minimal of
1.21 and predict 80 observables in 45 decays for future experimental data to
test. We then vary the unknown SU(3) amplitudes to obtain the allowed range of
branching ratios for the 8 undetermined decays. We find that some of them are
within reach of near future experimental capabilities. We urge our experimental
colleagues to carry out related searches.Comment: 9pages, 2 figures, 3 table
Review of the clinical applications and technological advances of circulating tumor DNA in cancer monitoring
DETC2005-84370 STUDY ON THE SENSITIVITY OF CONTROLLABLE PARAMETERS IN AN ACTIVE VIBRATION ISOLATION SYSTEM OF AIR SPRING WITH RUBBER BELLOW
ABSTRACT The characteristics of control parameters of air spring with rubber bellow are analyzed through finite element method and thermodynamic equation respectively. The analysis results indicate that the vertical stiffness of air spring is sensitive to the varying of vertical displacement and volume, and nonlinearly varies with vertical displacement. When the air spring is pressed down or pulled up under the exterior excitation, the height of air spring can be controlled to keep stable through adjusting the volume of air spring by the use of hydraulic transformer
Biochemical, haematological and histopathological studies of extract of Ageratum conyzoides L. in Sprague Dawley rats
This study was conducted to evaluate the safety potential of the leaf extract of Ageratum conyzoides Linnaeus in Sprague Dawley (SD) rats using biochemical, haematological and histological indices of toxicity. Four groups of seven male SD rats per group were used for the study. To group A was administered 0.25% CMC-Na/ kg body weight and was used as the control group, while groups B, C and D were respectively administered with 500, 1000 and 1500 mg/kg body weight of the ethanolic leaf extract of A. conyzoides by gastric intubation for 14 days. Animals were subsequently anaesthetized, blood samples were collected for biochemical and haematological assays; organs were isolated and weighed, while the liver, kidney and spleen were processed for histopathological studies. Aspartate
amino transferase, lactate dehydrogenase, creatine kinase and alkaline phosphatase were significantly (p < 0.05) reduced in the groups treated with 1000 and 1500 mg/kg body weight of the extract. Furthermore, there was a significant (p < 0.05) elevation in white blood cell count, mean platelet volume and % platelet distribution width. Histopathological studies indicated various degrees of hepatocellular necrosis in all the treated groups accompanied by significant increases in the weight of liver and spleen. The results showed that the ethanolic leaf extract of A. conyzoides significantly alters the
biomarkers of cardiac and skeletal muscle disorders, and higher doses could induce liver cell injury
Luminal B subtype: A key factor for the worse prognosis of young breast cancer patients in China
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