2,210 research outputs found
Locational determinants of the ICT sector across Italy
Is the rapid growth of the Information and Communication Technology (ICT) activities shaping new local specialization and industrial concentration? Does the analysis of local economic conditions help to explain the formation of âplacesâ specialized in ICT? We use 2001 Census data by Local Labour Systems (LLS) to investigate the characteristics of ICT specialization in Italy. Our investigation is based on a cross-sectional regression model using data for 686 LLS in which the dependent variable is an index of ICT local employment concentration. The measure of concentration we adopted is the location quotient (LQ) index. The LLS specialized in ICT activities in Italy account for 7.3% of total LLS. They are distributed all over the country, although those with highest LQ values are mainly in North-west and Central-south Italy. Our regression analysis provides the following results. The general econometric specification, i.e. that applied to all LLS, supports a positive and significant relationship between LLS specialized in some manufacturing industries (machinery, equipment and instruments; petrochemicals, rubber and plastic products; transport equipment; and paper, publishing and printing) or business services and relatively high localization of ICT employment. Besides, the model indicates that for LLS characterized by manufacturing SMEs there is a low probability of attaining a greater-than-the-national-average ICT employment specialization. These econometric results are in line with the general opinion that product specialization of Italian industries (the so-called âMade in Italyâ) and SMEs are less likely to be involved in ICT diffusion to business. Nevertheless, this pattern of results does not justify the interpretation that the industrial districts (where SMEs employment has the largest share) are at the origin of inadequate ICT diffusion to business in Italy. In fact, when the analysis is focused on industrial districts the results are slightly different. In particular, the variable SMEs does not produce a significant coefficient, while textile and clothing industries show a positive association with ICT, even though significant only at 10% level. What is the main policy implication of these empirical findings? National governmentâs policy makers should become aware that industrial districts are an appropriate instrument to promote the development of the ICT sector, although so far they have been neglected. "Information and Communication Technologies, Local Labour Systems, geographical concentration, local specialization
The associated production of tÂŻtH in ATLAS
Since its discovery in July 2012, it has become mandatory to study the couplings of the Higgs boson with other Standard Model particles. The associated production of Higgs and top-antitop pairs (tÂŻtH) gives direct access to the Higgs-top couplings. Due to the different decay modes of the tÂŻt pairs and of the Higgs boson, the process displays a large variety of decay channels involving in the final state, bÂŻb pairs, γγ and multileptonic (including Ï ) states. Although the sensitivity is still limited by the Run I statistics, the assessment of the analysis methods will be essential for constraining the t-H coupling using the data collected from 2015 at ATLAS at LHC. These include background estimation, selection optimization and
systematics control
On the effect of thermal ageing in CFRP mechanical properties
Highly Accelerated Life Testing (HALT) of any product consist in applying several types of loads for accelerated reliability analysis in order to find weaknesses during both design and development stages. Different environmental stress conditions like high rate thermal cycling and vibration are generally introduced during HALT. In this work, thermal cycles have been performed between -50 and 150°C for aeronautic composite materials in non-reactive and oxidative atmospheres. The thermal fatigue tests applied to polymer fibre reinforced composites involve matrix oxidation and cracking due to the mismatch of the thermal expansion coefficient between the carbon fibres and the epoxy matrix. In order to correlate the composite degradation with mechanical properties, fatigue and quasi-static tensile tests have been carried out in reference and post-ageing conditions. Microstructural characterization using X-ray computed tomography and light optical microscopy have been performed as well for a better understanding on damage mechanisms. Combined effect of thermal cycling and mechanical load tests on CFRP structural parts (T profile) were also performed
The phase II ATLAS Pixel: The Inner Tracker (ITk)
The ATLAS experiment is expected to enter the high-luminosity programme of the LHC (HL-LHC) with a thoroughly upgraded detector. This includes an all-silicon tracking system Inner Tracker (ITk) that will completely replace
the current Inner Detector. The innermost part of the ITk will consist of a five-layer pixel detector in the barrel region complemented by two end-caps characterized by
annular supports leading to an extended track reconstruction coverage. Different sensor technologies (planar, 3D and CMOS) are being investigated for instrumenting the detector, which will need to cope with the high occupancy and radiation level that are expected in the HL-LHC environment. For the same reason a new front-end
chip is being developed within the RD53 Collaboration. High data rates, expected in particular in the innermost layers, require the development of new technologies allowing high bandwidth transmission and handling
Symplectic algorithm for constant-pressure molecular dynamics using a Nose-Poincare thermostat
We present a new algorithm for isothermal-isobaric molecular-dynamics
simulation. The method uses an extended Hamiltonian with an Andersen piston
combined with the Nos'e-Poincar'e thermostat, recently developed by Bond,
Leimkuhler and Laird [J. Comp. Phys., 151, (1999)]. This
Nos'e-Poincar'e-Andersen (NPA) formulation has advantages over the
Nos'e-Hoover-Andersen approach in that the NPA is Hamiltonian and can take
advantage of symplectic integration schemes, which lead to enhanced stability
for long-time simulations. The equations of motion are integrated using a
Generalized Leapfrog Algorithm and the method is easy to implement, symplectic,
explicit and time reversible. To demonstrate the stability of the method we
show results for test simulations using a model for aluminum.Comment: 7 page
Stable superhydrophobic aluminum surfaces based on laser-fabricated hierarchical textures
Laser-microtextured surfaces have gained an increasing interest due to their enormous spectrum of applications and industrial scalability. Direct laser interference patterning (DLIP) and the well-established direct laser writing (DLW) methods are suitable as a powerful combination for the fabrication of single (DLW or DLIP) and multi-scale (DLW+DLIP) textures. In this work, four-beam DLIP and DLW were used independently and combined to produce functional textures on aluminum. The influence of the laser processing parameters, such as the applied laser fluence and the number of pulses, on the resulting topography was analyzed by confocal microscopy and scanning electron microscopy. The static long-term and dynamic wettability characteristics of the laser-textured surfaces were determined through water contact angle and hysteresis measurements, revealing superhydrophobic properties with static contact angles up to 163° and hysteresis as low as 9°. The classical Cassie-Baxter and Wenzel models were applied, permitting a deeper understanding of the observed wetting behaviors. Finally, mechanical stability tests revealed that the DLW elements in the multi-scale structure protects the smaller DLIP features under tribological conditions.Fil: Milles, Stephan. Technische UniversitĂ€t Dresden; AlemaniaFil: Dahms, Johannes. Technische UniversitĂ€t Dresden; AlemaniaFil: Soldera, Marcos Maximiliano. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Patagonia Norte. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas. Universidad Nacional del Comahue. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas; ArgentinaFil: Lasagni, AndrĂ©s F.. Technische UniversitĂ€t Dresden; Alemani
Tribocorrosion behavior of NiTi biomedical alloy processed by an additive manufacturing laser beam directed energy deposition technique
The purpose of the present study was to experimentally assess the synergistic effects of wear and corrosion on NiTi alloy in comparison with Ti-6Al-4V alloy, the most extensively used titanium alloy in biomedical applications. Both alloys were processed by an additive manufacturing laser beam directed energy deposition (LB-DED) technique, namely laser engineered net shaping (LENS), and analyzed via tribocorrosion tests by using the ball-on-plate configuration. The tests were carried out in phosphate buffered saline solution at 37 °C under open circuit potential (OCP) to simulate the body environment and temperature. The synergistic effect of wear and corrosion was found to result in an improved wear resistance in both materials. It was also observed that, for the process parameters used, the LB-DED NiTi alloy exhibits a lower tendency to corrosion as compared to the LB-DED Ti-6Al-4V alloy. It is expected that, during the service life as an implant, the NiTi alloy is less susceptible to the metallic ions release when compared with the Ti-6Al-4V alloy.This work was partially funded by FCT (Fundação para a CiĂȘncia e Tecnologia) through
the grant SFRH/BD/112280/2015 and the reference projects UID/EEA/04436/2019, COMPETE
2020 with the code POCI-01-0145-FEDER-006941; NORTE-01-0145-FEDER-000018-HAMaBICo and
POCI-01-0145-FEDER-031035_LaserMULTICER. Also, Coordenação de Aperfeiçoamento de Pessoal
de NĂvel Superior (CAPES-Brazil) and Alexander von Humboldt Foundation are acknowledged for
the partial support of this work. This work was also partially supported by the Project âEXPERTâ,
Contract no. 14PFE/17.10.2018 and Auburn Universityâs Presidential Award for Interdisciplinary
Research (PAIR)
Aspect ratio of nano/microstructures determines Staphylococcus aureus adhesion on PET and titanium surfaces
Aims: Joint infections cause premature implant failure. The avoidance of bacterial colonization of implant materials by modification of the material surface is therefore the focus of current research. In this in vitro study the complex interaction of periodic structures on PET and titanium surfaces on the adhesion of Staphylococcus aureus is analysed. Methods and Results: Using direct laser interference patterning as well as roll-to-roll hot embossing methods, structured periodic textures of different spatial distance were produced on surfaces and S. aureus were cultured for 24 h on these. The amount of adhering bacteria was quantified using fluorescence microscopy and the local adhesion behaviour was investigated using scanning electron microscopy. For PET structures, minimal bacterial adhesion was identified for an aspect ratio of about 0·02. On titanium structures, S. aureus adhesion was significantly decreased for profile heights of < 200 nm. Our results show a significantly decreased bacterial adhesion for structures with an aspect ratio range of 0·02 to 0·05. Conclusions: We show that structuring on surfaces can decrease the amount of S. aureus on titanium and PET as common implant materials. Significance and Impact of the Study: The study highlights the immense potential of applying specific structures to implant materials to prevent implant colonization with pathogen bacteria.Fil: Meinshausen, A. K.. Otto-von-Guericke-UniversitĂ€t Magdeburg; AlemaniaFil: Herbster, M.. Otto-von-Guericke-UniversitĂ€t Magdeburg; AlemaniaFil: Zwahr, C.. Technische UniversitĂ€t Dresden; AlemaniaFil: Soldera, Marcos Maximiliano. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Patagonia Norte. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas. Universidad Nacional del Comahue. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas; ArgentinaFil: MĂŒller, A.. Otto-von-Guericke-UniversitĂ€t Magdeburg; AlemaniaFil: Halle, T.. Otto-von-Guericke-UniversitĂ€t Magdeburg; AlemaniaFil: Lasagni, A. F.. Technische UniversitĂ€t Dresden; AlemaniaFil: Bertrand, J.. Otto-von-Guericke-UniversitĂ€t Magdeburg; Alemani
Conditioning of hiPSC-derived cardiomyocytes using surface topography obtained with high throughput technology
Surface functionalization of polymers aims to introduce novel properties that favor bioactive responses. We have investigated the possibility of surface functionalization of polyethylene terephthalate (PET) sheets by the combination of laser ablation with hot embossing and the application of such techniques in the field of stem cell research. We investigated the response of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) to topography in the low micrometer range. HiPSC-CMs are expected to offer new therapeutic tools for myocardial replacement or regeneration after an infarct or other causes of cardiac tissue loss. However, hiPSC-CMs are phenotypically immature compared to myocytes in the adult myocardium, hampering their clinical application. We aimed to develop and test a high-throughput technique for surface structuring that would improve hiPSC-CMs structural maturation. We used laser ablation with a ps-laser source in combination with nanoimprint lithography to fabricate large areas of homogeneous micron- to submicron line-like pattern with a spatial period of 3 ”m on the PET surface. We evaluated cell morphology, alignment, sarcomeric myofibrils assembly, and calcium transients to evaluate phenotypic changes associated with culturing hiPSC-CMs on functionalized PET. Surface functionalization through hot embossing was able to generate, at low cost, low micrometer features on the PET surface that influenced the hiPSC-CMs phenotype, suggesting improved structural and functional maturation. This technique may be relevant for high-throughput technologies that require conditioning of hiPSC-CMs and may be useful for the production of these cells for drug screening and disease modeling applications with lower costs.Fil: Cortella, Lucas R. X.. Universidade de Sao Paulo; BrasilFil: Cestari, IdĂĄgene A.. Universidade de Sao Paulo; BrasilFil: Lahuerta, Ricardo D.. Universidade de Sao Paulo; BrasilFil: Arana, Matheus C.. Universidade de Sao Paulo; BrasilFil: Soldera, Marcos Maximiliano. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Patagonia Norte. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas. Universidad Nacional del Comahue. Instituto de InvestigaciĂłn y Desarrollo en IngenierĂa de Procesos, BiotecnologĂa y EnergĂas Alternativas; ArgentinaFil: Rank, Andreas. Technische UniversitĂ€t Dresden; AlemaniaFil: Lasagni, AndrĂ©s F.. Technische UniversitĂ€t Dresden; AlemaniaFil: Cestari, Ismar N.. Universidade de Sao Paulo; Brasi
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