Internal structure of nanoparticles of Al generated by laser ablation in liquid ethanol

Al NPs are synthesized by laser ablation of a bulk Al target immersed into liquid ethanol saturated with hydrogen at atmospheric pressure. The nanoparticles possess a well-distinguished core-shell structure. High Resolution Transmission Electron Microscopy shows several layers inside the Al nanoparticle: oxide layer, amorphous Al, single crystal Al, and a cavity in the center. Formation of the cavity is attributed to the sharp increase of hydrogen dissolution in Al upon its melting and its eventual release after the solidification

Dynamics of ripple formation on silicon surfaces by ultrashort laser pulses in sub-ablation conditions

An investigation of ultrashort pulsed laser induced surface modification due to conditions that result in a superheated melted liquid layer and material evaporation are considered. To describe the surface modification occurring after cooling and resolidification of the melted layer and understand the underlying physical fundamental mechanisms, a unified model is presented to account for crater and subwavelength ripple formation based on a synergy of electron excitation and capillary waves solidification. The proposed theoretical framework aims to address the laser-material interaction in sub-ablation conditions and thus minimal mass removal in combination with a hydrodynamics-based scenario of the crater creation and ripple formation following surface irradiation with single and multiple pulses, respectively. The development of the periodic structures is attributed to the interference of the incident wave with a surface plasmon wave. Details of the surface morphology attained are elaborated as a function of the imposed conditions and results are tested against experimental data

Primary pigmented nodular adrenocortical disease presenting with a unilateral adrenocortical nodule treated with bilateral laparoscopic adrenalectomy: a case report

<p>Abstract</p> <p>Introduction</p> <p>Primary pigmented nodular adrenocortical disease is a rare cause of adrenocorticotropic hormone-independent Cushing's syndrome. We report an uncommon primary pigmented nodular adrenocortical disease case presenting with a unilateral adrenocortical nodule and provide a brief overview of the existing literature.</p> <p>Case presentation</p> <p>A 27-year-old Caucasian woman was admitted to our Department with adrenocorticotropic hormone-independent Cushing's syndrome. Its cause was initially considered a left adrenocortical adenoma based on computer tomography imaging. The patient underwent left laparoscopic adrenalectomy and histological examination revealed pigmented micronodular adrenal hyperplasia. Evaluation for the presence of Carney complex was negative. Six months later recurrence of hypercortisolism was documented and a right laparoscopic adrenalectomy was performed further establishing the diagnosis of primary pigmented nodular adrenocortical disease. After a nine-year follow-up there is no evidence of residual disease.</p> <p>Conclusions</p> <p>Even though primary pigmented nodular adrenocortical disease is a rare cause of Cushing's syndrome, it should be included in the differential diagnosis of adrenocorticotropic hormone-independent Cushing's syndrome, especially because adrenal imaging can be misleading mimicking other adrenocortical diseases. Bilateral laparoscopic adrenalectomy is the preferred treatment in these subjects.</p