Preparation and characterisation of titania/hydroxyapatite composite coatings obtained by sol-gel process

In the present work a titania network encapsulating a hydroxyapatite particulate phase is proposed as a bioceramic composite coating. The coating on a titanium substrate was produced starting from a sol containing a mixture of titania colloidal particles and hydroxyapatite submicron particles using the dip-coating technique. The microstructure, the morphology and the surface chemical composition of the coating were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. Adhesion tests were also performed. These analyses showed that the obtained coating was chemically clean, homogeneous, rough, porous, with a low thickness and well-defined phase composition as well as a good adhesion to the substrate. Copyright © 2001 Elsevier Science Ltd

Sustainable Production of Stiff and Crystalline Bacterial Cellulose from Orange Peel Extract

In this work, a potentially economic and environmentally friendly method for the synthesis of bacterial cellulose (BC) by Gluconacetobacter xylinus from a biomass containing orange peel extract was evaluated. Orange peel extract was used as a culture medium without any hydrolysis treatment, thus speeding up the synthesis procedure. The efficacy of orange peel as a carbon source was compared with that of sucrose. The orange peel extract formed thicker cellulose gels than those formed using sucrose. X-ray diffraction (XRD) revealed both a high crystallinity index and crystallite size of BC nanofibers in samples obtained from orange peel (BC_Orange). Field emission scanning electron microscopy (FE-SEM) revealed a highly densely packed nanofibrous structure (50 nm in diameter). BC_Orange presented a two-fold increase in water holding capacity (WHC), and dynamic mechanical analysis (DMA) showed a 44% increase in storage modulus compared to sucrose derived BC. These results showed that the naturally available carbon sources derived from orange peel extract can be effectively used for BC production. The orange-based culture medium can be considered a profitable alternative to the generation of high-value products in a virtuous circular economy model

Direct femtosecond laser fabrication of superhydrophobic aluminum alloy surfaces with anti-icing properties

Ice formation is a serious issue in many fields, from energy to aerospace, compromising the devices' efficiency and security. Superhydrophobicity has been demonstrated to be correlated to the anti-icing properties of surfaces. However, fabricating surfaces with robust water repellence properties also at subzero temperature is still a great challenge. In this work, femtosecond laser (fs-laser) texturing is exploited to produce superhydrophobic surfaces with anti-icing properties on Al2024, an aluminum alloy of great interest in cold environments, in particular for aircraft production. Our textured substrates present self-cleaning properties and robust water repellency at subzero temperatures. Moreover, outstanding anti-icing properties are achieved on the textured surfaces at-20 °C, with water droplets bouncing off the surface before freezing

Nanocrystalline TiO2 based films onto fibers for photocatalytic degradation of organic dye in aqueous solution

Nanocrystalline titania (TiO2) synthesized via sol–gel, by using an alkoxide precursor were deposited onto commercially available silica and alumina fibers, namely E-Glass and Nextel 650, respectively. Different processing conditions and material preparation parameters, such as amount of TiO2, film composition and annealing temperature were tested in order to obtain nanocrystalline TiO2 with different morphological and structural characteristics. The materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and the Brunauer, Emmett, and Teller (BET) surface area measurements. The photocatalytic activity of the obtained coated fibers was investigated by monitoring the degradation of a model molecule, an azo dye (Methyl Red), under UV irradiation in aqueous solution. The detected photocatalytic performance of the sol–gel derived nanocrystalline TiO2 was explained on the basis of mechanism associated to the photocatalytic decomposition of organic molecules using semiconductor oxides and accounted for the structural and morphological characteristics of the TiO2 based coating. The materials with the most suited characteristics for photocatalysis were used to scale up the deposition onto a larger sample of fiber and then tested in a photocatalytic reactor. A commercially available TiO2 standard material (TiO2 P25 Degussa) was used as reference, in order to ultimately assess the viability of the coating process for real application

Measurements and tests on FBK silicon sensors with an optimized electronic design for a CTA camera

In October 2013, the Italian Ministry approved the funding of a Research & Development (R&D) study, within the "Progetto Premiale TElescopi CHErenkov made in Italy (TECHE)", devoted to the development of a demonstrator for a camera for the Cherenkov Telescope Array (CTA) consortium. The demonstrator consists of a sensor plane based on the Silicon Photomultiplier (SiPM) technology and on an electronics designed for signal sampling. Preliminary tests on a matrix of sensors produced by the Fondazione Bruno Kessler (FBK-Trento, Italy) and on electronic prototypes produced by SITAEL S.p.A. will be presented. In particular, we used different designs of the electronics in order to optimize the output signals in terms of tail cancellation. This is crucial for applications where a high background is expected, as for the CTA experiment.Comment: 5 pages, 6 figures; Proceedings of the 10th Workshop on Science with the New Generation of High-Energy Gamma-ray experiments (SciNeGHE) - PoS(Scineghe2014)00

A Prototype of a New Generation Readout ASIC in 65 nm CMOS for Pixel Detectors at HL-LHC

The foreseen High-Luminosity upgrade at the CERN Large Hadron Collider (LHC) will constitute a new frontier for particle physics after year 2024, demanding for the installation of new silicon pixel detectors able to withstand unprecedented track densities and radiation levels in the inner tracking systems of current general-purpose experiments. This paper describes the implementation of a new-generation pixel chip demonstrator using a commercial 65 nm CMOS technology and targeting HL-LHC specifications. It was designed as part of the Italian INFN CHIPIX65 project and in close synergy with the international CERN RD53 collaboration on 65 nm CMOS. The prototype is composed of a matrix of 64×64 pixels with 50 μm × 50 μm cells featuring a compact design, low-noise and low-power performance. The pixel array integrates two different analogue front-end architectures working in parallel, one with asynchronous and one with synchronous hit discriminators. Common characteristics are a compact layout able to fit into half the pixel size, low-noise performance (ENC < 100 e− RMS for 50 fF input capacitance), below 5 μW/pixel power consumption, linear charge measurements up to 30 ke− input charge using Time-over-Threshold (ToT) encoding and leakage current compensation up to 50 nA per pixel. A novel region-based digital architecture has been designed in order to ensure > 99% efficiency for expected 3 GHz/cm2 hit rate, 1 MHz trigger rate and 12.5 μs trigger latency at HL-LHC. Pixels have been organized into regions of 4×4 cells and a common synthesized logic shared among all pixels provides a centralized memory for latency buffering, performs the trigger matching and handles the local configuration. The simulated particle inefficiency for this architecture is below 0.1% under nominal HL-LHC conditions. All global biases and voltages required by analogue front-ends are generated on-chip using 10-bit programmable DACs. Bias currents and voltages can be monitored by a 12-bit ADC. A bandgap voltage reference circuit provides a stable reference voltage for all these blocks. The readout of triggered data is based on replicated FIFOs placed at the chip periphery. Data are finally sent off-chip with 8b/10b encoding using a high-speed serializer. Triggerless and debug operating modes are also supported. Chip configuration and slow-control are performed through fully-duplex synchronous Serial Peripheral Interface (SPI) master/slave transactions. The I/O interface uses custom-designed JEDEC-compliant SLVS transmitters and receivers. All blocks and analogue front-ends have been silicon-proven during a previous prototyping phase and were demonstrated to be radiation tolerant up to 580 Mrad Total Ionizing Dose (TID) or beyond. The CHIPIX65 demonstrator was submitted for fabrication on July 2016. It was received back from the foundry on October 2016 and preliminary experimental characterizations started

UTRdb and UTRsite (RELEASE 2010) : a collection of sequences and regulatory motifs of the untranslated regions of eukaryotic mRNAs

The 5' and 3' untranslated regions of eukaryotic mRNAs (UTRs) play crucial roles in the post-transcriptional regulation of gene expression through the modulation of nucleo-cytoplasmic mRNA transport, translation efficiency, subcellular localization and message stability. UTRdb is a curated database of 5' and 3' untranslated sequences of eukaryotic mRNAs, derived from several sources of primary data. Experimentally validated functional motifs are annotated and also collated as the UTRsite database where more specific information on the functional motifs and cross-links to interacting regulatory protein are provided. In the current update, the UTR entries have been organized in a gene-centric structure to better visualize and retrieve 5' and 3'UTR variants generated by alternative initiation and termination of transcription and alternative splicing. Experimentally validated miRNA targets and conserved sequence elements are also annotated. The integration of UTRdb with genomic data has allowed the implementation of an efficient annotation system and a powerful retrieval resource for the selection and extraction of specific UTR subsets. All internet resources implemented for retrieval and functional analysis of 5' and 3' untranslated regions of eukaryotic mRNAs are accessible at http://utrdb.ba.itb.cnr.it/

A Prototype of a New Generation Readout ASIC in 65 nm CMOS for Pixel Detectors at HL-LHC

The foreseen High-Luminosity upgrade at the CERN Large Hadron Collider (LHC) will constitute a new frontier for particle physics after year 2024, demanding for the installation of new silicon pixel detectors able to withstand unprecedented track densities and radiation levels in the inner tracking systems of current general-purpose experiments. This paper describes the implementation of a new-generation pixel chip demonstrator using a commercial 65 nm CMOS technology and targeting HL-LHC specifications. It was designed as part of the Italian INFN CHIPIX65 project and in close synergy with the international CERN RD53 collaboration on 65 nm CMOS. The prototype is composed of a matrix of 64×64 pixels with 50 μm × 50 μm cells featuring a compact design, low-noise and low-power performance. The pixel array integrates two different analogue front-end architectures working in parallel, one with asynchronous and one with synchronous hit discriminators. Common characteristics are a compact layout able to fit into half the pixel size, low-noise performance (ENC < 100 e− RMS for 50 fF input capacitance), below 5 μW/pixel power consumption, linear charge measurements up to 30 ke− input charge using Time-over-Threshold (ToT) encoding and leakage current compensation up to 50 nA per pixel. A novel region-based digital architecture has been designed in order to ensure > 99% efficiency for expected 3 GHz/cm2 hit rate, 1 MHz trigger rate and 12.5 μs trigger latency at HL-LHC. Pixels have been organized into regions of 4×4 cells and a common synthesized logic shared among all pixels provides a centralized memory for latency buffering, performs the trigger matching and handles the local configuration. The simulated particle inefficiency for this architecture is below 0.1% under nominal HL-LHC conditions. All global biases and voltages required by analogue front-ends are generated on-chip using 10-bit programmable DACs. Bias currents and voltages can be monitored by a 12-bit ADC. A bandgap voltage reference circuit provides a stable reference voltage for all these blocks. The readout of triggered data is based on replicated FIFOs placed at the chip periphery. Data are finally sent off-chip with 8b/10b encoding using a high-speed serializer. Triggerless and debug operating modes are also supported. Chip configuration and slow-control are performed through fully-duplex synchronous Serial Peripheral Interface (SPI) master/slave transactions. The I/O interface uses custom-designed JEDEC-compliant SLVS transmitters and receivers. All blocks and analogue front-ends have been silicon-proven during a previous prototyping phase and were demonstrated to be radiation tolerant up to 580 Mrad Total Ionizing Dose (TID) or beyond. The CHIPIX65 demonstrator was submitted for fabrication on July 2016. It was received back from the foundry on October 2016 and preliminary experimental characterizations started

ASPicDB: a database of annotated transcript and protein variants generated by alternative splicing

Alternative splicing is emerging as a major mechanism for the expansion of the transcriptome and proteome diversity, particularly in human and other vertebrates. However, the proportion of alternative transcripts and proteins actually endowed with functional activity is currently highly debated. We present here a new release of ASPicDB which now provides a unique annotation resource of human protein variants generated by alternative splicing. A total of 256 939 protein variants from 17 191 multi-exon genes have been extensively annotated through state of the art machine learning tools providing information of the protein type (globular and transmembrane), localization, presence of PFAM domains, signal peptides, GPI-anchor propeptides, transmembrane and coiled-coil segments. Furthermore, full-length variants can be now specifically selected based on the annotation of CAGE-tags and polyA signal and/or polyA sites, marking transcription initiation and termination sites, respectively. The retrieval can be carried out at gene, transcript, exon, protein or splice site level allowing the selection of data sets fulfilling one or more features settled by the user. The retrieval interface also enables the selection of protein variants showing specific differences in the annotated features. ASPicDB is available at http://www.caspur.it/ASPicDB/

p53FamTaG: a database resource of human p53, p63 and p73 direct target genes combining in silico prediction and microarray data

<p>Abstract</p> <p>Background</p> <p>The p53 gene family consists of the three genes p53, p63 and p73, which have polyhedral non-overlapping functions in pivotal cellular processes such as DNA synthesis and repair, growth arrest, apoptosis, genome stability, angiogenesis, development and differentiation. These genes encode sequence-specific nuclear transcription factors that recognise the same responsive element (RE) in their target genes. Their inactivation or aberrant expression may determine tumour progression or developmental disease. The discovery of several protein isoforms with antagonistic roles, which are produced by the expression of different promoters and alternative splicing, widened the complexity of the scenario of the transcriptional network of the p53 family members. Therefore, the identification of the genes transactivated by p53 family members is crucial to understand the specific role for each gene in cell cycle regulation. We have combined a genome-wide computational search of p53 family REs and microarray analysis to identify new direct target genes. The huge amount of biological data produced has generated a critical need for bioinformatic tools able to manage and integrate such data and facilitate their retrieval and analysis.</p> <p>Description</p> <p>We have developed the p53FamTaG database (p53 FAMily TArget Genes), a modular relational database, which contains p53 family direct target genes selected in the human genome searching for the presence of the REs and the expression profile of these target genes obtained by microarray experiments. p53FamTaG database also contains annotations of publicly available databases and links to other experimental data.</p> <p>The genome-wide computational search of the REs was performed using PatSearch, a pattern-matching program implemented in the DNAfan tool. These data were integrated with the microarray results we produced from the overexpression of different isoforms of p53, p63 and p73 stably transfected in isogenic cell lines, allowing the comparative study of the transcriptional activity of all the proteins in the same cellular background.</p> <p>p53FamTaG database is available free at <url>http://www2.ba.itb.cnr.it/p53FamTaG/</url></p> <p>Conclusion</p> <p>p53FamTaG represents a unique integrated resource of human direct p53 family target genes that is extensively annotated and provides the users with an efficient query/retrieval system which displays the results of our microarray experiments and allows the export of RE sequences. The database was developed for supporting and integrating high-throughput <it>in silico</it> and experimental analyses and represents an important reference source of knowledge for research groups involved in the field of oncogenesis, apoptosis and cell cycle regulation.</p