Directed assembly of optically bound matter

We present a study of optically bound matter formation in a counter-propagating evanescent field, exploiting total internal reflection on a prism surface. Small ensembles of silica microspheres are assembled in a controlled manner using optical tweezers. The structures and dynamics of the resulting optically bound chains are interpreted using a simulation implementing generalized Lorentz-Mie theory. In particular, we observe enhancement of the scattering force along the propagation direction of the optically bound colloidal chains leading to a microscopic analogue of a driven pendulum which, at least superficially, resembles Newton’s cradle

Interparticle interactions:Energy potentials, energy transfer, and nanoscale mechanical motion in response to optical radiation

In the interactions between particles of material with slightly different electronic levels, unusually large shifts in the pair potential can result from photoexcitation, and on subsequent electronic excitation transfer. To elicit these phenomena, it is necessary to understand the fundamental differences between a variety of optical properties deriving from dispersion interactions, and processes such as resonance energy transfer that occur under laser irradiance. This helps dispel some confusion in the recent literature. By developing and interpreting the theory at a deeper level, one can anticipate that in suitable systems, light absorption and energy transfer will be accompanied by significant displacements in interparticle separation, leading to nanoscale mechanical motion

Long period fiber gratings made in active fibers: rigorous analysis and its experimental verification

The presented novel and rigorous analysis, which includes grating-assisted diffraction of amplified spontaneous emission generated along the entire grating structure, predicts accurately performance of the studied devices in terms of both the amplitude and phase.</p

Hypertriglyceridemic Waist -a Simple Clinical Tool to Detect Cardiometabolic Risk: Comparison With Harmonized Definition of Metabolic Syndrome

Summary With the increasing prevalence of obesity and especially abdominal obesity, a simple clinical tool is needed that identifies the cardiometabolic risk for cardiovascular disease and type 2 diabetes. The aim of our study was to evaluate a broad spectrum of metabolic variables and IMT in subjects with and without hypertriglyceridemic waist (HTGW) and compare it with the harmonized definition of metabolic syndrome (MS) with both a higher (MS-I) and lower waist circumference (MS-II) for Europids. We enrolled 607 asymptomatic dyslipidemic subjects (295 men and 312 women) into our cross-sectional study. The subjects with HTGW had an atherogenic lipid profile (significantly higher triglycerides, AIP, non-HDL-C, lower HDL-C and ApoA-1, and the women also higher TC and ApoB), increased markers of insulin resistance (insulin, HOMA, C-peptide, proinsulin), inflammation (hsCRP), thrombosis (fibrinogen, PAI-1), SBP and DBP, and lower adiponectin (p&lt;0.05-0.001 for all). These risk factors were entirely similar in HTGW, MS-I and MS-II. Age-adjusted IMT was significantly higher only in the women with HTGW but this significance disappeared after further adjustment for TC, SBP, and smoking. Our results support the routine use of HTGW as a simple and inexpensive screening tool to detect subjects at increased cardiometabolic risk in clinical practice