Interaction between torsional deformation and mobile charges in a composite rod of piezoelectric dielectrics and nonpiezoelectric semiconductors

We propose a type of polarization-independent circulator based on a composite rod of ferrite and plasma materials in a two-dimensional photonic crystal (PhC) slab. Only one composite rod was set at the center of the structure to provide circulation for both TE- and TM-polarized waves. Additionally, to improve the performance of the circulator, three additional rods were inserted to improve the coupling condition between the center magneto-optical microcavity and the corresponding waveguides. Finite element method was used to calculate the characteristics of the structure and the Nelder–Mead optimization method was employed to obtain the optimum parameters. The results show that a low insertion loss (~0.22 dB) and high isolation (~14 dB) can be achieved in our structure for waves of both TE and TM polarizations. The idea presented here may be useful for designing compact polarization devices in large-scale integrated photonic circuits.

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Association arterial stiffness reduction with improved left ventricular longitudinal and torsional deformation after 3 years of antihypertensive treatment

European Heart Journal ◽

10.1093/ehjci/ehaa946.2759 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

S Tzortzis ◽

I Ikonomidis ◽

H Triantafyllidi ◽

J Thymis ◽

A Frogoudaki ◽

...

Keyword(s):

Blood Pressure ◽

Arterial Stiffness ◽

Ace Inhibitors ◽

Antihypertensive Treatment ◽

Left Ventricular ◽

Torsional Deformation ◽

Flow Reserve ◽

Stiffness Reduction ◽

Arterial Blood ◽

Lv Mass

Abstract Background We investigated the effects of antihypertensive treatment on vascular function, longitudinal and torsional deformation in hypertensives. Methods In 200 untreated patients with arterial hypertension (age 52.5±11.6 years, 56% females), we measured at baseline and after a 3-year of antihypertensive treatment (160 received ACEi± diuretics and 40 CCBs± diuretics): a) 24h ambulatory blood pressure b) Carotid-femoral pulse wave velocity (PWV) b) Coronary flow reserve (CFR), LV mass index (LVMI), the global longitudinal strain (GLS) and diastolic (LongSRSE) strain rate, peak twisting (Tw-deg) and untwisting at mitral valve opening (UtwMVO), at peak E (UtwE) and at the end of the E wave (UtwendE) of the mitral inflow as well as twisting (TwVel-deg/sec) velocity using speckle tracking imaging. We calculated the % change of LV untwisting as difference between peakTw and UtwMVO, UtwpeakE and UtwendE. Results Compared to baseline, there was an improvement of GLS (−19.9±3.4 vs. −18.7±3.1%), LongSRS (−1.08±0.22 vs. −0.98±0.26 1/s), LongSRE (1.09±0.36 vs. 0.99±0.31 1/s), peak Tw (16.2±5.1 vs. 18.7±5.9 deg), Tw velocity, and the %LV untwisting (31.04±19.28 vs 26.02±15.69% at MVO, 60.04±19.78 vs 53.96±19.76% at peakE and 79.98±14.24 vs 75.90±17.01% at endE) post-treatment. In parallel, CFR (2.72±0.61 vs. 2.55±0.64), PWV (10.34±1.93 vs. 11.2±2.08 m/s) and LVMI were improved (p<0.01 for all comparisons). By ANOVA, the interaction term between changes of all the above parameters and antihypertensive treatment (ACE inhibitors vs calcium channel blockers) was not significant (p>0.05). By multivariate analysis, the reduction of 24h meanBP and PWV independently determined the respective improvement of GLS (b=0.478 and b=0.248 respectively), LongS (b=0.428 and b=0.201 respectively) as well as Twisting (b=0.449 and b=0.294 respectively) after adjusting for changes in LV mass, CFR and atherosclerotic risk factors (p<0.05). Conclusions Long-term optimal blood pressure control with ACE inhibitors and CCBs improves LV longitudinal and torsional mechanics in hypertensives in parallel with arterial stiffness and blood pressure. This improvement in LV deformation and twisting was independently related to changes in arterial blood pressure and arterial stiffness. Funding Acknowledgement Type of funding source: None

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Experimental Analysis of Static Stiffness for Vehicle Body in White

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.248.69 ◽

2012 ◽

Vol 248 ◽

pp. 69-73 ◽

Cited By ~ 2

Author(s):

Shu Ming Chen ◽

Xue Wei Song ◽

Chuan Liang Shen ◽

Deng Feng Wang ◽

Wei Li

Keyword(s):

Test Bench ◽

Bending Stiffness ◽

Torsional Stiffness ◽

Vehicle Body ◽

Torsional Angle ◽

Static Stiffness ◽

Torsional Deformation ◽

Automotive Body ◽

Body In White ◽

Stiffness Characteristics

In order to know the static stiffness characteristics of the vehicle body in white, the bending stiffness and torsional stiffness of an automotive body in white were tested on a test bench of the static stiffness of an automotive BIW. The bending stiffness and bending deformation of the bottom of the BIW were determined. Also, the torsional stiffness and torsional deformation of the bottom of the BIW were obtained. The fitting curves and equations between loading torque and torsional angle were acquired at clockwise and counterclockwise loading, respectively.

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Co-casting and optical characteristics of transparent segmented composite Er:YAG laser ceramics

Journal of Materials Research ◽

10.1557/jmr.2010.0069 ◽

2010 ◽

Vol 25 (3) ◽

pp. 476-483 ◽

Cited By ~ 47

Author(s):

Elizabeth R. Kupp ◽

Gary L. Messing ◽

Julie M. Anderson ◽

Venkatraman Gopalan ◽

John Q. Dumm ◽

...

Keyword(s):

Er:Yag Laser ◽

Casting Process ◽

Composite Ceramic ◽

Laser Operation ◽

Lasing Wavelength ◽

Laser Gain ◽

Composite Rod ◽

Ceramic Laser ◽

Transparent Composite ◽

First Time

A novel colloidal co-casting process was developed to fabricate laser quality, multisegment composite ceramic laser gain materials. The approach was demonstrated for a three segment transparent composite rod 62 mm long by 3 mm diameter consisting of undoped yttrium aluminus garnet (YAG), 0.25% Er:YAG, and 0.5% Er:YAG. The Er concentration profile in the composite has steep, controllable gradients at the segment interfaces, while maintaining constant dopant concentrations within each segment. The composite rod has 84% transmittance at 1645 nm (the lasing wavelength) with a scatter loss of 0.4% cm−1. Laser operation of such a composite Er:YAG ceramic rod was demonstrated for the first time, with nearly equivalent lasing behavior to an Er:YAG single crystal rod.

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