ABSTRACT
While a broadband metamaterial perfect absorber (MPA) has been implemented and proposed intensively in recent years, an ultra-broadband perfect absorber with polarization selectivity has not been realized in literature. In this work, we propose a configuration of polarization-selective (PS) MPA with ultra-wide absorption bandwidth. The aluminum wire grid is integrated on top of the ultrathin-metal-dielectric stacking. The transverse electric (TE) wave is blocked due to the requirement of zero tangential electric field at the metal surface. The transverse magnetic field can pass the aluminum wire-grids because the normal electric field can be supported by the surface charge density at the metal surface, and full absorption of the TM wave is accomplished by the metal-dielectric stacking beneath. Theoretical calculation using rigorously coupled wave analysis demonstrates the wavelength selectivity from λ = 1.98µm to λ = 11.74µm where the TE absorption is <0.04 while TM absorption is >0.95, using 300 nm thick aluminum (Al) wire grid with 16-pair SiO2/Ti stacking. Additionally, the design is wavelength scalable by adjusting the dielectric thickness (tSiO2) and the wire grid period (P) and height (t). The experimental result is demonstrated using Al grids and Ti/SiO2, and the measured result fully supports the calculated prediction.
ABSTRACT
<p><b>OBJECTIVE</b>To compare the platelet-leukocyte-aggregates (PLAs) level among patients with acute coronary syndrome (ACS) and stable angina pectoris (SAP).</p><p><b>METHODS</b>Hospitalized patients were divided into three groups [ACS group (n=86), SAP group (n=54), the control group with 46 patients without coronary artery disease]. PLAs were measured by flow cytometry at admission before coronary angiography. ACS patients were further divided into low-risk group (0-108 points) and high-risk group (>109 points) according to GRACE scores at admission. PLA, platelet-monocyte aggregations (PMA), platelet-neutrophil aggregations (PNA), platelet-lymphocyte aggregations (PlyA) and hs-CRP values were compared among groups.</p><p><b>RESULTS</b>PLA (4.40%±3.08%), PMA (33.6%±21.5%), PNA (3.76%±5.06%), PLyA (2.03%±1.27%) and hs-CRP [5.75 (3.49, 9.15)] levels in ACS group were significantly higher than those in SAP and control groups (all P<0.05). PLA was also significantly higher in high-risk group than in the low-risk group (44.8%±18.0% vs. 13.0%±6.3%, P<0.01). Spearman correlation analysis showed that hs-CRP was positively correlated with PMA (r=0.547, P<0.01) and GRACE score is positively correlated with PMA, PLA, PNA and PlyA (r=0.746, 0.652, 0.460, respectively, all P<0.01).</p><p><b>CONCLUSION</b>PLAs is increased in ACS patients and higher PMA level is related with the unstable coronary syndrome in ACS patients. Increased PMA, PLA, PNA and PlyA levels is associated with higher GRACE score in ACS patients.</p>
