Comparative Study of Calculated LDL-Cholesterol Levels with the Direct Assay in Patients with Hypothyroidism.

Background Hypothyroidism is one among the many factors that predisposes one to coronary artery disease. As low-density lipoprotein-cholesterol (LDL-C) is associated with cardiovascular risk, calculated LDL-C should have good accuracy with minimal bias. Hypothyroidism alters the lipid composition of lipoproteins by the secretion of triglyceride-rich lipoproteins, which affects the calculation of LDL-C. The present study aimed to compare 13 different formulae for the calculation of LDL-C including the newly derived Martin's formula by direct assay in patients of hypothyroidism. Method In this analytical cross-sectional study, a total of 105 patients with laboratory evidence of hypothyroidism, from January to June 2019, were studied, and blood samples were subjected for lipid profile analysis at central biochemistry laboratory. Calculated LDL-C was assessed by different formulae. Result We observed that calculated LDL-C by Friedewald's, Cordova's, Anandaraja's, Hattori's, and Chen's formulae has bias less than ± 5 compared with direct LDL-C, with Anandaraja's formula having the lowest bias (2.744) and Cordova's formula having lowest bias percentage (-1.077) among them. According to the Bland-Altman plots, the bias in Friedewald's and Anandraja's were equally distributed below and above the reference line of direct LDL-C. Conclusion This is the first study comparing different formulae for LDL-C calculation in patients with hypothyroidism. Anandaraja's formula was as equally effective as Friedewald's formula when used as an alternative cost-effective tool to evaluate LDL-C in hypothyroid patients. The recently proposed Martin's formula for calculated LDL-C had a higher bias when compared with Friedewald's and Anandaraja's formulae in patients with hypothyroidism.

Subpicosecond pre-plasma dynamics of a high contrast, ultraintense laser-solid target interaction.

Using the spectral interferometry technique, we measured subpicosecond time-resolved pre-plasma scale lengths and early expansion (<12 ps) of the plasma produced by a high intensity (6 × 1018 W/cm2) pulse with high contrast (109). We measured pre-plasma scale lengths in the range of 3-20 nm, before the arrival of the peak of the femtosecond pulse. This measurement plays a crucial role in understanding the mechanism of laser coupling its energy to hot electrons and is hence important for laser-driven ion acceleration and the fast ignition approach to fusion.

Enhanced x-ray emission from nano-particle doped bacteria.

Recently, it has been greatly appreciated that intense light matter interaction is modified due to the nano- and microstructures in the target by--surface plasmons, laser energy localization scattering etc. Extreme laser intensities produce dense plasmas and collective mechanisms generate energetic electrons, ions and hard x-rays. Recently, it is postulated that the anharmonic electron motion, driven by ultrashort, high-intensity laser pulses, provides a universal mechanism for the laser absorption. Here, we provide the first demonstration of anharmonic-resonance-aided high laser-absorption in a biological system. At intensities of ∼ 10¹6⁻¹8 W/cm², 40 fs pulses excite a plasma formed with E. coli bacteria. The density-inhomogeneities due to the micro- and nanostructures in the bacterial target increase anharmonic resonance (AHR) heating and result in a 104-fold enhancement in the hard x-ray yield compared to plain solid targets. These observations lead to novel high-energy x-ray sources that have implications to lithography, imaging and medical applications.

Ultrafast optics of solid density plasma using multicolor probes.

We present time-resolved reflectivity and transmissivity of hot, overdense plasma by employing a multicolor probe beam, consisting of harmonics at wavelengths of 800 nm, 400 nm and 266 nm. The hot-dense plasma, formed by exciting a fused silica target with a 30 fs, 2 × 10(17) W cm(-2) intensity pulse, shows a sub-picosecond transition in reflectivity (transmissivity), and a wavelength-dependent fall (rise) in the reflected (transmitted) signal. A simple model of probe absorption in the plasma via inverse bremsstrahlung is used to determine electron-ion collision frequency at different plasma densities.

Real-time study of fast-electron transport inside dense hot plasmas.

We offer a method to study transport of fast electrons in dense hot media. The technique relies on temporal profiling of the laser induced magnetic fields and offers a unique capability to map the hot electron currents and their neutralization (or lack of it) by the return currents in the plasma. We report direct quantitative measurements of strong electric inhibition in insulators and turbulence induced anomalous stopping of hot electrons in conductors. The present technique can prove extremely important from the point of view of fast ignition scheme, which relies on the penetration of fast electrons into the fusion core.