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A number of disordered systems exhibit local anisotropy in the fractal or multifractal correlation and in the resulting scaling behavior, which contain wealth of information on the system. Here, we demonstrate that the spatial dielectric fluctuations in a random medium like biological tissue exhibit such multifractal anisotropy, leaving its unique signature in the wavelength variation of the light scattering Mueller matrix and manifesting as an intriguing spectral diattenuation effect.We have thus developed an inverse analysis method for the quantification of the multifractal anisotropy from the scattering Mueller matrix. The method is based on processing the relevant Mueller matrix elements in Fourier domain using Born approximation followed by multifractal analysis. Application of this technique on tissues of human cervix ex vivo demonstrate the potential of the multifractal anisotropy parameters as novel biomarkers for screening subtle micro-structural changes associated with precancers. Sensing structural anisotropy in the submicron length scale via the multifractal anisotropy parameters may prove valuable for noninvasive characterization of a wide class of complex materials and disordered scattering media.

Fourier domain low coherence interferometry is a promising method for quantification of the depth distribution of the refractive index in a layered scattering medium such as biological tissue. Here, we have explored backscattering spectral interferometric measurement in combination with multifractal detrended fluctuation analysis to probe and quantify multifractality in depth distribution of the refractive index in tissue. The depth resolution of the experimental system was validated on model systems comprising of polystyrene microspheres and mica sheet, and was initially tested on turbid collagen layer, the main building blocks of the connective tissue. Following successful evaluation, the method was applied on ex vivo tissues of human cervix. The derived multifractal parameters of depth-resolved index fluctuations of tissue, namely, the generalized Hurst exponent and the width of the singularity spectrum showed interesting differences between tissues having different grades of precancers. The depth-resolved index fluctuations exhibited stronger multifractality with increasing pathological grades, demonstrating its promise as a potential biomarker for precancer detection.

Thyrotoxic periodic paralysis (TPP) is an endocrine emergency. In initial hours, it requires multidisciplinary care as it involves heart and nervous system. Early diagnosis demands highest clinical acumen as symptoms and signs of thyrotoxicosis are often subtle. TPP is not nowadays confined to particular ethnic groups. Different cellular ion channels have been identified in its etiopathogenesis. Definitive treatment of thyrotoxicosis is also important to prevent relapse. In all cases of hypokalemia in emergency room, TPP should be excluded. Management of hypokalemia should be rationalized to prevent rebound hyperkalemia as total body potassium loss is minimum or nil. Patients should be made euthyroid as soon as possible to prevent relapse of TPP. Future research on ethnic variation of Na + -K + ATPase activity may enlighten us the cause of higher prevalence in Asians.