Regularized cost function in wavefront shaping for advancing the contrast of structured light.

The cost function in the iterative optimization algorithms is one of the sensitive optimization controllers that plays a crucial role in feedback based wavefront shaping for constructing well-resolved complex structured light through scattering media. There has been a trade-off between resolution and the contrast enhancement of the structured light in wavefront shaping. We have developed an ℓ 2-norm based quadratic cost function (L2QN) and proposed a regularized cost function (RCF) for advancing the contrast and maintaining the high resolution of structured light. Both the simulations and experiments have been performed, and it has been found that the proposed RCF significantly advances the contrast and structural uniformity for focusing light through scattering media as well as for diffused reflection mode. The potential applications of the method demonstrated in this study can be extended into holographic displays, structured light illumination microscopy, photo-lithography, photothermal treatments, dosimetry, laser materials processing, and energy control inside and outside an incubation system.

The effect of norepinephrine on clinical and hemodynamic parameters in neonates with shock: a retrospective cohort study.

There is limited data on the cardiovascular effects of norepinephrine (NE) in neonates. Our objective was to describe the clinical responses in neonates treated with NE infusion. This retrospective cohort study included neonates with evidence of shock and those who received NE infusion. PRIMARY OUTCOME: changes in mean blood pressure (MBP) at 6, 12, and 24 h post-initiation of NE. SECONDARY OUTCOMES: Changes in (i) diastolic BP, systolic BP, and vasoactive inotrope score (VIS) at 6, 12, and 24 h, (ii) urine output after initiation of NE ii) pH, lactate, fraction of inspired oxygen (FiO2) after initiation of NE, and (iv) adverse outcomes. Fifty infants received NE with mean (SD) gestational age of 34.3 (4.3) weeks and a mean birth weight of 2215 (911) g. Treatment began at a median age of 36 (IQR: 15.2, 67.2) hours of life and lasted 30.5 (IQR: 12.7, 58) hours. MBP improved from 34.4 mm Hg (SD: 6.6) at baseline to 39.4 mm Hg (SD: 10.5, p < 0.001) at 6 h, to 39.6 mm Hg (SD: 12.1, p = 0.002) at 12 h and to 40.4 mm Hg (SD: 15.5, p = 0.004) at 24 h after NE initiation. Vasoactive inotrope score declined from 30 (20, 32) to 10 (4, 30; p < 0.001) at 24 h. Urine output improved within 24 h [1.5 ml/kg/h (0.5, 2.3) at baseline to 3 (1.9, 4.3) at 24 h; p = 0.04]. Oxygen requirement decreased after NE initiation. CONCLUSION: The use of NE appears to be effective and safe for treating systemic hypotension in neonates. TRIAL REGISTRATION: Being a retrospective study, trial registration was not considered. WHAT IS KNOWN: • Dopamine has traditionally been used as the initial agent for treatment of neonatal hypotension. • Norepinephrine has recently been recommended as the first-choice vasopressor agent to correct hypotension in adults and pediatric patients, with insufficient data on the cardiovascular effects of NE in neonates What is new: • Mean blood pressure improved significantly at 6, 12, and 24 h with reduction in vasoactive infusion score at 12 and 24 h after norepinephrine infusion. • No significant change in heart rate or abnormal abdominal adverse effects noted in this study.

Formation of multiple complex light structures simultaneously in 3D volume using a single binary phase mask.

Complex structure formation inside or through turbid media is a challenging task due to refractive index inhomogeneity, random light scattering, and speckle noise formation. In this article, we have coupled the data regression model in the R-squared metric and used its advantages as a fitness function in the genetic algorithm to advance the resolution and structural uniformity. As a compatible system with the binary genetic algorithm, we have presented a cost-effective iterative wavefront shaping system-design with binary phase modulation using an affordable ferroelectric liquid crystal (FLC) based binary-phase spatial light modulator (SLM). R-squared metric in the genetic algorithm is analyzed to optimize the binary phase mask, and the prototype system based on iterative binary phase modulation has been validated with a 120-grit ground glass diffuser and fresh chicken tissues of thickness 307 [Formula: see text] and 812 [Formula: see text]. The detailed results show that the proposed cost-effective wavefront shaping system with data regression model assisted R-squared fitness function can construct high-resolution multiple complex hetero-structures simultaneously in 3D volume using an optimized single phase-mask.