Neuroblastoma cells displacement by magnetic carbon nanotubes

In this paper, as-produced multiwall carbon nanotubes (MWNTs) have been analyzed by scanning electron microscopy and energy dispersive X-ray spectrometry, revealing the presence of Fe, Al, and Zn residuals and impurities. MWNTs have then been dispersed in Pluronic F127 aqueous solution and used to seed neuroblastoma cell lines (HN9.10e and SH-SY5Y) for three days. We found that MWNTs interact with cells and induce, under a permanent constant magnetic field, the cell displacement toward the magnetic source.     

CMOS Non‐tailed differential pair

A continuous‐time complementary metal–oxide–semiconductor differential pair that does not require the traditional tail current source as a way to control the direct current and common‐mode current is presented. Compared with a p‐channel long‐tailed pair, the proposed non‐tailed solution operates under a higher maximum input common‐mode voltage that includes (V_DD + V_SS)/2 even under low supply voltages. Experimental measurements on a prototype fabricated in a 0.35‐µm technology (with metal – oxide – semiconductor thresholds greater than 0.6 V) confirm this behavior for supply voltages as low as 1.2 V, whereas the long‐tailed pair with the same technology offers the same capability only for supplies higher than 1.6 V. Copyright © 2015 John Wiley & Sons, Ltd.     

Development and in vitro characterization of chitosan-based microspheres for nasal delivery of promethazine

Conventional and composed promethazine-loaded microspheres were prepared by spray drying of chitosan solution systems and double water-in-oil-in-water (W/O/W) emulsion systems, respectively. Double emulsions were prepared in two different feed concentrations, with chitosan dissolved in both water phases, and ethylcellulose dissolved in oil phase. Swelling and bioadhesive properties of the microspheres depended on the chitosan content, type and the feed concentration of spray-dried system. Results obtained suggested that better ethylcellulose microcapsules with promethazine in the chitosan matrix were formed when less concentrated emulsion systems were spray-dried. Thus, in case of such a system, with ethylcellulose/chitosan weight ratio of 1:2, prolonged promethazine release was obtained.     

Selection of single domain binding proteins by covalent DNA display

Selection technologies such as phage and ribosome display, which provide a physical linkage between genetic information and encoded polypeptide, are important tools for the engineering of proteins for diagnostic and therapeutic applications. We have recently described a selection strategy called covalent DNA display, in which individual proteins are covalently linked to the cognate encoding DNA template in separate droplets of a water-in-oil emulsion. We here report on the optimization of several experimental steps in covalent DNA display technology, such as the elution conditions and the PCR strategy used for the amplification of selected DNA templates. A PCR assembly strategy was developed, which allows the amplification of the DNA templates over repeated rounds of selection. In addition, we could demonstrate that approximately 50% of the DNA templates form a covalent adduct with the corresponding proteins in the compartments of a water-in-oil emulsion. In model selection experiments, differences in recovery efficiency <100 000 per round of selection could be observed when comparing a specific binding polypeptide with a binder of irrelevant specificity. Furthermore, the optimized protocol was successfully applied for the selection of single domain proteins, capable of specific binding to mouse serum albumin (MSA). A mutant derived from the SH3 domain of the Fyn kinase, with millimolar affinity to MSA, was affinity matured using covalent DNA display and yielded several MSA binding FynSH3 variants with dissociation constants in the 100 nM range.     

Mediterranean diet and the metabolic syndrome

The metabolic syndrome (also referred to as syndrome X or the insulin resistance syndrome) has emerged as an important cluster of risk factors for atherosclerotic disease. Patients with the syndrome also are at increased risk for developing type 2 diabetes mellitus. Common features are central (abdominal) obesity, insulin resistance, hypertension, and dyslipidemia. Weight reduction deserves first priority in individuals with abdominal obesity and the metabolic syndrome. Both weight reduction and maintenance of a lower weight are best achieved by a combination of reduced caloric intake and increased physical activity. Dietary patterns close to the Mediterranean diet and rich in fruit and vegetables, and high in monounsaturated fats are negatively associated with features of the metabolic syndrome. Some recent studies dealing specifically with the effect of interventions on the resolution of the metabolic syndrome have demonstrated a 25% net reduction in the prevalence of the syndrome following lifestyle changes mainly based on nutritional recommendations. Similar rates of resolution have been obtained with drugs, such as rosiglitazone and rimonabant. The favourable benefit/hazard ratio makes Mediterranean-style diets particularly promising to reduce the cardiovascular burden associated with the metabolic syndrome.     

Free security tools: Pros and Cons: A review of free security tools

Open Source is now an established phenomenon: basic products such as LINUX, “x” BSD and BeOS are already widely available. There are two main factors driving this expansion: costs are very low and it is relatively simple — though not exactly within everyone's capabilities — to implement an infrastructure based on software completely supported by the international community, with no purchase costs. For this reason, operators have recently focused their attention on system and network management products, with particular emphasis on security.     

Learning and Evolution

In the last few years several researchers have resorted to artificial evolution (e.g., genetic algorithms) and learning techniques (e.g., neural networks) for studying the interaction between learning and evolution. These studies have been conducted for two different purposes: (a) looking at the performance advantages obtained by combining these two adaptive techniques; (b) understanding the role of the interaction between learning and evolution in biological organisms. In this paper we describe some of the most representative experiments conducted in this area and point out their implications for both perspectives outlined above. Understanding the interaction between learning and evolution is probably one of the best examples in which computational studies have shed light on problems that are difficult to study with the research tools employed by evolutionary biology and biology in general. From an engineering point of view, the most relevant results are those showing that adaptation in dynamic environments gains a significant advantage by the combination of evolution and learning. These studies also show that the interaction between learning and evolution deeply alters the evolutionary and the learning process themselves, offering new perspectives from a biological point of view. The study of learning within an evolutionary perspective is still in its infancy and in the forthcoming years it will produce an enormous impact on our understanding of how learning and evolution operate.     

Monitoring of perfluorinated compounds in edible fish from the Mediterranean Sea

Perfluorooctanoic acid (PFOA) and perfluorooctane sulphonate (PFOS) are environmental contaminants belonging to a chemical group known as perfluorinated compounds (PCFs). The United States Environmental Protection Agency (US EPA) considers both compounds to be carcinogenic. The goal of the present study was to evaluate the contamination levels of PFOS and PFOA in edible fish of the Mediterranean Sea. Twenty six fish muscles, 17 fish livers, five series of cephalopods (each composed of ten specimens) and thirteen series of bivalves (each composed of about 50 specimens) were used for the investigation. A fast sample treatment, followed by an LC–ESI–MS/MS method is described for the identification, and quantification of PFOA and PFOS in fish. The method was in-house-validated through the determination of precision, accuracy, specificity, calibration curve, decision limit (CCα), and detection capability (CCβ). The results showed PFOA and PFOS levels in fishes and molluscs lower than those reported for analogue matrices in different geographic areas. Therefore, our biomonitoring results did not show that the Mediterranean Sea had any particularly alarming pollution by PFCs, although it is located in a semi-closed basin with scarce water change. Nonetheless, a worrying element is that a few fish showed extremely high contamination by PFOA and PFOS. This finding needs further clarification in order to assess whether such unusual contamination is linked to “dot-like” pollutant release, which could explain the anomaly.     

Experimental characterization of focusing by high-numerical-aperture zone plates

High-numerical-aperture zone plates have important applications in high-resolution optical maskless lithography as well as scanning confocal microscopy. We describe two methods to experimentally characterize the focusing properties, i.e., the point-spread function, of such diffractive lenses. The first method uses spot exposures in photoresist and the second uses a conventional knife-edge scan. The experimental results agree well with rigorous theoretical calculations.