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This article introduces novel tools to automatically generate pertinent Ada values in order to produce higher quality tests for Ada subprograms. A first tool will generate valid Ada values based on a structural analysis of the types of the parameters of the subprogram under test following various customizable strategies. Those values will then be filtered in order to satisfy the specifications of the subprogram, and new coverage criteria for executable specifications will be used to assess the relevance of the generated testsuite. This first set of values will then be used as seeds both for a fuzzing process, and a symbolic execution campaign, from which values of interest will be then extracted. This integrated process will enable users to generate a high value starting test corpus, which can then be expanded upon by domain-specific tests. [ABSTRACT FROM AUTHOR]

In this study, ZnO thin films have been electrodeposited from zinc nitrate solution without using any catalyst, additive, or seed layer on two kinds of substrates (Si and ITO glass). Using cyclic voltammetry and chronoamperometry, it was shown that the mechanism of ZnO deposition strongly depends on the substrate used and its overpotential for nitrate reduction. On Si, the nitrate reduction into nitrite occurs before that of Zn. This reaction induces an increase of the local pH leading to ZnO precipitation. In contrast on ITO, the Zn reduction brings first metallic Zn deposition, which is then chemically oxidized by nitrate into ZnO phase. The effect of deposition time on morphology, structure, and photoluminescence properties was studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) measurements. The chemical nature of the substrate has no influence on the orientation of nanorods, but really impacts their morphology and the optical emission properties. X-ray diffraction analysis always revealed ZnO wurtzite phase with a (002) preferential orientation enhanced with increasing deposition time. A well-defined ZnO morphology was generated under −1.4 V for 60 min on Si and ITO glass. ZnO nanorods that composed the nanoflowers grown on ITO glass tend to be shorter, wider, and with higher aspect ratio than on Si. ZnO nanostructures prepared on ITO showed an intense UV emission without spreading in the visible region, thus demonstrating the formation of a defect free structure. [ABSTRACT FROM AUTHOR]

Porous Al2O3 films were deposited on copper thin film templates onto silicon substrates by means of pulsed laser deposition (PLD) technique using a KrF excimer laser. The copper films have been first deposited in vacuum on Si substrates at room temperature, with a particular distribution of Cu droplets to favour pores formation. Alumina deposition has been done following ablation of a pure Al target at 10-3 Torr oxygen pressure at different substrate temperatures: room temperature, 600 °C and 650 °C. The characterization of samples involved micro-Raman spectroscopy, FTIR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM) and energy dispersive x-ray spectroscopy (EDS) to reveal structural and morphological properties. FTIR and Raman spectroscopy results corroborated with EDS analyses confirm the presence of alumina in the Al2O3/Cu/Si structures. SEM images show 300 nm ordered pores in films deposited at room temperature. [ABSTRACT FROM AUTHOR]

Surface treatments are considered as a good alternative to increase biocompatibility and the lifetime of Ti-based alloys used for implants in the human body. The present research reports the comparison of bare and modified Ti6Al4V substrates on hydrophilicity and corrosion resistance properties in body fluid environment at 37 °C. Several surface treatments were conducted separately to obtain either a porous oxide layer using nanostructuration (N) in ethylene glycol containing fluoride solution, or bulk oxide thin films through heat treatment at 450 °C for 3 h (HT), or electrochemical oxidation at 1 V for 3 h (EO), as well as combined treatments (N-HT and N-EO). In-situ X-ray diffraction and ex-situ transmission electron microscopy have shown that heat treatment gave first rise to the formation of a 30 nm thick amorphous layer which crystallized in rutile around 620 °C. Electrochemical oxidations gave rise to a 10 nm thick amorphous film on the top of the surface (EO) or below the amorphous nanotube layer (N-EO). Dual treated samples presented similar results with a more stable behavior for N-EO. Finally, for both corrosion and hydrophilicity points of view, the new combined treatment to get a total amorphous N-EO sample seems to be the best and even better than the partially crystallized N-HT sample.

Arthroplasty is a surgical procedure to restore the function of the joint of patient suffering from knee osteoarthritis. However, postoperative functional deficits are reported even after a rehabilitation program. In order to determine the origin of functional deficits of patient suffering from knee osteoarthritis and total knee arthroplasty, we developed a rodent model including a chemically-induced-osteoarthritis and designed a knee prosthesis (Ti6Al4V/PEEK) biomechanically and anatomically adapted to rat knee joint. Dynamic Weight-Bearing, gait kinematics, H-reflex from vastus medialis muscle and activities from metabosensitive III and IV afferent fibers in femoral nerve were assessed at 1 and 3 months post-surgery. Results indicate that knee osteoarthritis altered considerably the responses of afferent fibers to their known activators (i.e., lactic acid and potassium chloride) and consequently their ability to modulate the spinal sensorimotor loop, although, paradoxically, motor deficits seemed relatively light. On the contrary, results indicate that, after the total knee arthroplasty, the afferent responses and the sensorimotor function were slightly altered but that motor deficits were more severe. We conclude that neural changes attested by the recovery of the metabosensitive afferent activity and the sensorimotor loop were induced when a total knee replacement was performed and that these changes may disrupt or delay the locomotor recovery.

Due to their high specific surface area and advanced properties, TiO 2 nanotubes (TiO 2 NTs) have a great significance for production and storage of energy. In this paper, TiO 2 NTs were synthesized from anodization of Ti-6Al-4V alloy at 60 V for 3 h in fluoride ethylene glycol electrolyte by varying the water content and further annealing treatment. The morphological, structural, optical and electrochemical performances of TiO 2 NTs were investigated by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), UV-Visible spectroscopy and electrochemical characterization techniques. By varying the water content in the solution, a honeycomb and porous structure was obtained at low water content and the presence of (α + β) phase in Ti-6Al-4V alloy caused not uniform etching. With an additional increase in water content, a nanotubular structure is formed in the (α + β) phases with different morphological parameters. The anatase TiO 2 NTs synthesized with 20 wt% H 2 O shows an improvement in absorption band that extends into the visible region due the presence of vanadium oxide in the structure and the effective band gap energy ( Eg ) value of 2.25 eV. The TiO 2 NTs electrode also shows a good cycling performance, delivering a reversible capacity of 82 mAh.g -1 (34 μAh.cm -2 .μm -1 ) at 1C rate over 50 cycles.

Background: Red blood cells (RBCs) contain large amounts of iron, and periodic therapeutic phlebotomy is thus the main treatment for hereditary hemochromatosis (HH). However, the donation of therapeutic phlebotomy products from asymptomatic patients for transfusion purposes remains controversial. In this study, we compared the quality of RBCs obtained from HH patients with those of non-HH RBCs, within the allowed 42-day storage period., Study Design and Methods: RBCs were obtained from HH patient donors and random regular blood donors by whole blood collection. RBCs were stored for up to 42 days, according to national regulations and standard blood bank conditions in France. The following variables were assessed: hematologic and biochemical results, RBC membrane and soluble inflammatory markers, and the proinflammatory potential of HH RBC supernatant toward endothelial cells in an in vitro model., Results: There were no major differences between the two groups in terms of biophysical, biochemical, or soluble immunomodulatory factors. However, we observed small but significant differences in changes in RBC membrane proteins during storage, including increased phosphatidylserine expression and decreased hemolysis in HH compared with normal RBCs. However, there were no differences in terms of bioactivity of soluble immunomodulatory factors in the RBC supernatant during storage between HH and control donors, as determined by their effects on endothelial cells in vitro., Conclusions: These in vitro studies suggest that RBCs from HH patients appear, while exhibiting subtle differences, to be suitable for transfusion purposes according to currently accepted criteria., (© 2016 AABB.)

We report the electrochemical performance of porous NASICON-type Li3Fe2(PO4)3 thin films to be used as a cathode for Li-ion microbatteries. Crystalline porous NASICON-type Li3Fe2(PO4)3 layers were obtained by radio frequency sputtering with an annealing treatment. The thin films were characterized by XRD, SEM, and electrochemical techniques. The chronoamperometry experiments showed that a discharge capacity of 88 mAhg(-1) (23 μAhcm(-2)) is attained for the first cycle at C/10 to reach 65 mAhg(-1) (17 μAhcm(-2)) after 10 cycles with a good stability over 40 cycles.

The synthesis of a conformal poly(3,4-ethylenedioxythiophene) (PEDOT) layer on Si nanowires was demonstrated using a pulsed electrodeposition technique. N-type Si nanowire (SiNWs) arrays were synthesized using an electroless metal-assisted chemical etching technique. The dependence of the SiNW reflection on the concentration of the AgNO3 solution was identified. A reflection of less than 2% over the entire visible spectral range was obtained for these structures, evidencing their excellent antireflective properties. The etched SiNWs nanostructures can be further modified by using a tapering technique, which further preserves the strong light trapping effect. P-type PEDOT was grown on these SiNWs using electrochemical methods. Since the polymerization reaction is a very fast process with regards to monomer diffusion along the SiNW, the conformal deposition by classical, fixed potential deposition was not favored. Instead, the core-shell heterojunction structure was finally achieved by a pulsed deposition method. An extremely large shunt resistance was exhibited and determined to be related to the diffusion conditions occurring during polymerization.

The highly conformal electrodeposition of a copolymer electrolyte (PMMA-PEO) into self-organized titania nanotubes (TiO2nt) is reported. The morphological analysis carried out by scanning electron microscopy and transmission electron microscopy evidenced the formation of a 3D nanostructure consisting of a copolymer-embedded TiO2nt. The thickness of the copolymer layer can be accurately controlled by monitoring the electropolymerization parameters. X-ray photoelectron spectroscopy measurements confirmed that bis(trifluoromethanesulfone)imide salt was successfully incorporated into the copolymer electrolyte during the deposition process. These results are crucial to fabricate a 3D Li-ion power source at the micrometer scale using TiO2nt as the negative electrode.