Production of lipid microparticles containing bioactive molecules functionalized with PEG

The functionalization of bioactive principles is a relevant issue as it allows increasing their stability, to raise the hydrophilic properties of hydrophobic materials, to reduce the absorption from macrophages and the proteolytic degradation. For this reason, we have functionalized a model protein (Ribonuclease A) with polyethylene glycol (PEG₅₀₀₀).We have investigated the production of lipid/PEG particles incorporating this active principle by a supercritical fluid technology (particles from gas saturated solution, PGSS) to obtain solid micro- and nanoparticles.Runs were carried out to study the process conditions; thus, the effects of the operative variables, such as temperature, pressure and organic solvent, were optimized to obtain micrometric particles.The particles produced were characterized by static light scattering (SLS) to determine their mean and distribution size. The better operative conditions were employed to produce microparticles incorporating Ribonuclease A (RNAse) as both native and PEGylated form.The BCA test was applied to determine the maximum amount of protein incorporated in the particles and the in vitro release. The retained enzymatic activity of proteins after the PEGylation and after the micronization process was also determined by spectrophotometric evaluation.     

Novel Electrocardiographic Patterns for the Prediction of Hypertensive Disorders of Pregnancy—From Pathophysiology to Practical Implications

Hypertensive disorders of pregnancy are a major cause of poor outcome, including placental abruption, organ failure, cerebrovascular accident and disseminated intravascular coagulation. These disorders are associated with increased fetal risk of intrauterine growth restriction, intrauterine death and prematurity. Electrocardiography (ECG) recently emerged as a useful tool to evaluate cardiovascular complications during pregnancy. Specifically, left atrial abnormalities detected by standard ECG are associated with a fourfold increased risk of developing hypertensive disorders during pregnancy. The mechanisms linking left atrial abnormality on ECG with hypertensive disorders are still elusive. Several mechanisms, possibly reflected by abnormal left atrial activation on ECG, has been suggested. These include increased reactivity to angiotensin II and up-regulation of angiotensin type 1 receptors, with activation of autoantibodies targeting these receptors.     

New EXAFS Measurements by XEOL and TEY on Porous Silicon

Results of an EXAFS investigation on porous Silicon carried out by X-ray Excited Optical Luminescence (XEOL) and Total Electron Yield (TEY) techniques, at the Si K absorption edge, are reported. For the first time XEOL spectra of porous silicon have been recorded in a wide energy range (1800–2500 eV) and EXAFS signals have been singled out from them. Simultaneous TEY and XEOL measurements yield to different results: in particular TEY-EXAFS is sensitive up to the third coordination shell of Si, while XEOL-EXAFS reveals only the contributions of the first two coordination shells; moreover they show a different dependence on changes of the etching parameters. This evidences the sensitivity of XEOL technique to the local structure of the quantum confined luminescent sites. The dependence of the light emission properties on the main preparation parameters and their influence on the short-range structure of red and yellow porous silicon samples are also investigated.     

Determining and characterizing the reused text for plagiarism detection

An important task in plagiarism detection is determining and measuring similar text portions between a given pair of documents. One of the main difficulties of this task resides on the fact that reused text is commonly modified with the aim of covering or camouflaging the plagiarism. Another difficulty is that not all similar text fragments are examples of plagiarism, since thematic coincidences also tend to produce portions of similar text. In order to tackle these problems, we propose a novel method for detecting likely portions of reused text. This method is able to detect common actions performed by plagiarists such as word deletion, insertion and transposition, allowing to obtain plausible portions of reused text. We also propose representing the identified reused text by means of a set of features that denote its degree of plagiarism, relevance and fragmentation. This new representation aims to facilitate the recognition of plagiarism by considering diverse characteristics of the reused text during the classification phase. Experimental results employing a supervised classification strategy showed that the proposed method is able to outperform traditionally used approaches.     

High order harmonic generation: The role of the acceleration matrix elements and of the bound and continuum transitions

Abstract

The electromagnetic spectrum emitted by a one-dimensional atom driven by a strong laser field is obtained by use of the acceleration form and interpreted by means of few general properties of the matrix elements of the acceleration operator. We show that the emission occurs essentially in a region near the atomic core where the acceleration is significant and we investigate the role of the various emission channels arising from interference effects between transitions involving the bare atomic levels.