Identification and Validation of a New Set of Five Genes for Prediction of Risk in Early Breast Cancer

Molecular tests predicting the outcome of breast cancer patients based on gene expression levels can be used to assist in making treatment decisions after consideration of conventional markers. In this study we identified a subset of 20 mRNA differentially regulated in breast cancer analyzing several publicly available array gene expression data using R/Bioconductor package. Using RTqPCR we evaluate 261 consecutive invasive breast cancer cases not selected for age, adjuvant treatment, nodal and estrogen receptor status from paraffin embedded sections. The biological samples dataset was split into a training (137 cases) and a validation set (124 cases). The gene signature was developed on the training set and a multivariate stepwise Cox analysis selected five genes independently associated with DFS: FGF18 (HR = 1.13, p = 0.05), BCL2 (HR = 0.57, p = 0.001), PRC1 (HR = 1.51, p = 0.001), MMP9 (HR = 1.11, p = 0.08), SERF1a (HR = 0.83, p = 0.007). These five genes were combined into a linear score (signature) weighted according to the coefficients of the Cox model, as: 0.125FGF18 − 0.560BCL2 + 0.409PRC1 + 0.104MMP9 − 0.188SERF1A (HR = 2.7, 95% CI = 1.9–4.0, p < 0.001). The signature was then evaluated on the validation set assessing the discrimination ability by a Kaplan Meier analysis, using the same cut offs classifying patients at low, intermediate or high risk of disease relapse as defined on the training set (p < 0.001). Our signature, after a further clinical validation, could be proposed as prognostic signature for disease free survival in breast cancer patients where the indication for adjuvant chemotherapy added to endocrine treatment is uncertain.     

FPGA implementation of dynamic channel assignment algorithm for cognitive wireless sensor networks

The reliability of wireless sensor networks (WSNs) in industrial applications can be thwarted due to multipath fading, noise generated by industrial equipment or heavy machinery and particularly by the interference generated from other wireless devices operating in the same spectrum band. Recently, cognitive WSNs (CWSNs) were proposed to improve the performance and reliability of WSNs in highly interfered and noisy environments. In this class of WSN, the nodes are spectrum aware, that is, they monitor the radio spectrum to find channels available for data transmission and dynamically assign and reassign nodes to low-interference condition channels. In this work, we present the implementation of a channel assignment algorithm in a field-programmable gate array, which dynamically assigns channels to sensor nodes based on the interference and noise levels experimented in the network. From the results obtained from the performance evaluation of the CWSN when the channel assignment algorithm is considered, it is possible to identify how many channels should be available in the network in order to achieve a desired percentage of successful transmissions, subject to constraints on the signal-to-interference plus noise ratio on each active link.     

Effect of Seed Addition on SnO2‐Based Varistors for Low Voltage Application

The effect of seed addition on the microstructure and non‐ohmic properties of the SnO₂ + 1%CoO + 0.05%Nb₂O₅ ceramic‐based system was analyzed. Two classes of seeds were prepared: 99% SnO₂ + 1%CuO and 99% SnO₂ + 1%CoO (mol%); both classes were added to the ceramic‐based system in the amount of 1%, 5%, and 10%. The two systems containing 1% of seeds resulted in a larger grain size and a lower breakdown voltage. The addition of 1% copper seeds produces a breakdown voltage (V_b) of ~ 37 V and a leakage current (f_ic) of 29 μA. On the other hand, the addition of 1% cobalt seeds produced a breakdown voltage of 57 V and a leakage current of 70 μA. Both systems are of great technological interest for low voltage varistor applications, by means of appropriate strategies to reduce the leakage current. Using larger amounts of seeds was not effective since the values of breakdown voltage in both cases are close to a system without seeds. To our knowledge, there are no reports in the literature regarding the use of seeds in the SnO₂ system for low voltage applications. A potential barrier model which illustrates the formation of oxygen species (O′_2(ads), O′_ads, and O″_ads) at the expense of clusters near the interface between grains is proposed.     

Synthesis of functional poly(styrene)‐block‐(methyl methacrylate/methacrylic acid) by homogeneous reverse atom transfer radical polymerization: Spherical nanoparticles,thermal behavior,self‐aggregation,and morphological properties

This study investigates the use of homogeneous reverse atom transfer radical polymerization for the synthesis of polystyrene (PS) initiated by conventional radical peroxide with copper bromide in the lower oxidation state and a 2,2′‐bypyridine complex as the catalyst. In a second stage, an amphiphilic block copolymer containing methyl methacrylate (MMA) was synthesized via normal atom transfer radical polymerization in two steps, followed by partial hydrolysis of the methyl ester linkage of the MMA block under acidic conditions. The block copolymer PS₆₉₉‐b‐P(MMA₂₃₂/MAA₅₈) obtained had a narrow molecular weight dispersity (Ð < 1.3). The structure of the precursor, PS‐b‐PMMA, and resultant polymer, was characterized and verified by FTIR and ¹H‐NMR spectroscopy as well as size exclusion chromatography. The self‐aggregation of PS₆₉₉‐b‐P(MMA₂₃₂/MAA₅₈) in organic solvents was monitored by UV spectroscopy, whereas the morphology and size of the formed microaggregates were investigated by transmission electron microscopy and dynamic light scattering. The results indicate that this copolymer formed regular spherical reverse micelles with a core–shell structure. The atomic force micrographs of PS₆₉₉‐b‐P(MMA₂₃₂/MAA₅₈) showed a rough surface morphology owing to microphase separation of the block copolymer. In addition, thermal characterization was performed by differential scanning calorimetry and thermogravimetric analysis. The glass transition temperature of PS₆₉₉‐b‐P(MMA₂₃₂/MAA₅₈) decreased significantly (65°C), when compared to PS and PMMA, suggesting that an enhanced movement of the polymer chains resulted by the segregation of the hydrolyzed P(MMA₂₃₂/MAA₅₈) block. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Carbon nanopatterns and nanoribbons from directly nanoimprinted polyacrylonitrile: Correlation between crystallite orientation and nanoimprint process

We present the fabrication of lithographically defined carbon patterns and nanoribbons using a common carbon precursor, polyacrylonitrile (PAN). This method is based on nanoimprint lithography and has been demonstrated to be reliable and capable of nanofabrication over a large surface area at low cost, compared with current carbon-patterning techniques. Most interestingly, the deformation profile of the PAN during the imprinting process resulted in a distribution of aligned PAN chains within the patterns, which led to a similar anisotropic correlation of the carbon crystallites in the carbonized structures.     

FUNCTIONALIZED CHITOSAN AND ITS USE IN PHARMACEUTICAL,BIOMEDICAL, AND BIOTECHNOLOGICAL RESEARCH

Hybrids of natural polymers with synthetic polymers are of great interest because of their application as biomedical and biodegradable materials. One of the natural polymers that has attracted much recent attention is chitosan, a polysaccharide obtained by alkaline deacetylation of chitin, exhibiting excellent biological properties such as biodegradability in the human body and immunological, antibacterial, and wound-healing activities. Chitosan has also been found to be a good candidate as a support material for gene delivery, cell culture, and tissue engineering. In this review we have presented the current applications of the various types of chitosan derivatives synthesized in the fields of drug delivery, tissue engineering, wound healing, antimicrobials, biotechnology, pharmaceutics, and cosmetics.     

ISOLATION AND CHARACTERIZATION OF PARAFFINIC COMPONENTS FROM VENEZUELAN ASPHALTS EFFECTS OF PARAFFIN DOPANTS ON RHEOLOGICAL PROPERTIES OF SOME ASPHALTS

ABSTRACT

Paraffinic concentrates were isolated from a couple of Venezuelan asphalts, one paraffinic in nature and the other naphteno-aromatic Multigram scale isolation required two steps. The first one was the separation of neutral hydrocarbons by means of soxhlet extractors filled with clay and extracted with hot cyclohexane. The second step comprised the cryogenic wax crystallization and filtration from neutral hydrocarbons diluted in methyl ethyl ketone, brought to -10°C. Typical operations comprised 800g of asphalt and recovery of 20g of waxes.     

Design of piezoelectric nanogenerator based on BiFeO3/epoxy resin with potential application for wearable electronic devices

Growing demand for electric energy in newly developed electronic systems causes increasing interest in research on piezoelectric nanogenerators (PENGs). Design and fabrication of such devices is challenging, considering cost of materials used in their construction. This is the main reason why intensive research has begun on 0-3 composites with piezoelectric properties. One of the most promising constituent materials for composites fabrication are polymers, due to their low cost and easy processing. Herein, we present fabricated wearable PENG with good impact and vibration energy conversion properties. Correlation between matrix stiffness and piezoelectric properties of 0-3 type composite is proposed. It was found that composite with 10 wt.% of BiFeO₃ particles exhibits power output density for vibrations, finger tapping, and air stream pressure P = 11.12 nW cm⁻³, P = 4.83 μW cm⁻³, and P = 769.2 μW cm⁻³, respectively. Decrease in stiffness of epoxy matrix results at least in two-times lower power output density for this same PENG. The obtained results demonstrate that the fabricated BFO/epoxy composites show the wide applicability and potential to be integrated with other functional devices, for example, as a part of wearable devices in smart shoes.     

The sensory evaluation of 2,4,6‐trichloroanisole in wines

This work proposes a sensory method to verify the ‘cork taint’ defect in food and beverages. This off‐flavour has considerable economic impact in wine but occasionally can occur in other food and beverages. In wine, 2,4,6‐trichloroanisole (TCA) is generally considered to be the main compound responsible for this taint. It is an easily recognized compound because of its low sensorial threshold, and it is described as a mouldy and damp cardboard odour. This sensory method, developed in wine, consists of specific panel training to recognize TCA in a series of olfactory tests. The effectiveness of the panel was tested with contaminated wines in which the TCA content had been previously determined by Solid Phase Microextraction‐Gas Chromatography Mass Spectrometry (SPME‐GC/MS) analysis. This sensory method is useful to train a panel able to recognize the ‘cork taint’ defect in different situations (legal appraisals or quality assurance systems). The use of a reliable sensory assay can reduce the number of chemical analyses and the proposed method can be applied to other beverages such as beer. Copyright © 2015 The Institute of Brewing & Distilling     

Radioactivity measurements and radiation dose evaluation in tap waters of Central Italy

Consumption of drinking water is very important for human nutrition and its quality must be strictly controlled. A study of radioactivity content in tap water samples collected in the Central Italy was performed in order to check the compliance with recent European regulations. Gross alpha and beta activity, 226Ra, 238U and 234U concentrations were measured. Gross alpha and beta activities were determined by standard ISO 9696 and ISO 9697; for 226Ra determination liquid scintillation was used. 238U and 234U concentrations were determined by alpha spectrometry after separation from matrix by extraction chromatography and electroplating. Recommended WHO guideline activity concentrations for drinking water (0.1 and 1.0 Bq/L for gross alpha and gross beta activity, respectively) are exceeded in two cases for gross alpha activity and are not exceeded in any case for gross beta activity. The concentrations (mBq/L) of 226Ra, 238U and 234U ranged from <1.70 to 15.3, 0.65 to 48.8 and 0.780 to 51.5, respectively. Effective dose due to the uranium isotopes and radium was calculated for children and adults using the dose coefficients reported by EC Directive 96/29 EURATOM and annual water intake. For all class ages, the doses are quite similar and much lower than 0.1 mSv/year.