Enhancing Magnesium Bioactivity for Biomedical Applications: Effects of Laser Texturing and Sandblasting on Surface Properties.

Magnesium and its alloys, valued for their lightweight and durable characteristics, have garnered increasing attention for biomedical applications due to their exceptional biocompatibility and biodegradability. This work introduces a comparison of advanced and basic methods-laser texturing and sandblasting-on magnesium surfaces to enhance bioactivity for biomedical applications. Employing a comprehensive analysis spanning surface morphology, hardness, wettability, tribological performance, and corrosion behavior, this study elucidates the intricate relationship between varied surface treatments and magnesium's performance.

Influence of Oil Viscosity on the Tribological Behavior of a Laser-Textured Ti6Al4V Alloy.

Laser texturing with a dimple pattern was applied to modify a Ti6Al4V alloy at the micro level, aiming to improve its friction and wear resistance in combination with oil lubrication to optimize the performance in demanding industrial environments. The tribological analysis was performed on four different dimple-textured surfaces with varying dimple size and dimple-to-dimple distance and under lubrication with three different oils, i.e.

Tribological Evaluation of Vegetable Oil/MoS Nanotube-Based Lubrication of Laser-Textured Stainless Steel.

In the present work, the functionalisation of austenitic stainless steel, AISI 316L surfaces via nanosecond Nd:YAG laser texturing in order to modify the surface morphology with crosshatch and dimple patterns is presented. A tribological analysis under lubrication with sunflower and jojoba oil with and without the addition of a solid lubricant, MoS nanotubes, was performed. In conjunction with friction/wear response laser-textured surface wettability, oil spreadability and oil retention capacity were also analysed.

Behavioural and biochemical responses of the sea snail Tritia reticulata to lithium concentration gradient.

Lithium (Li) is present in many modern technologies, most notably in rechargeable batteries. Inefficient recycling strategies for electronic waste containing this element may result in its release into aquatic systems, which may induce harmful effects on wildlife. The present study evaluated the effect of Li contamination on the gastropod Tritia reticulata exposed to different concentrations of Li (100, 200, 500 and 1000 µg L) for 21 days.

The Influence of Plasma Treatment on the Corrosion and Biocompatibility of Magnesium.

In our study, plasma surface modification was employed to tailor the surface properties of magnesium in terms of surface chemistry, topography, and wettability. For two sets of samples, the plasma treatment involved two steps using two different gases (hydrogen and oxygen), while one set of samples was treated with one step only using oxygen. X-ray photoelectron spectroscopy (XPS) was applied to determine the surface composition, oxidation state of the elements, and the thickness of the surface oxide layer on the Mg samples after different plasma treatments.

Simple through-plane spatial filter for 2D MRI projections.

A simple spatial filter for 2D projection MR imaging is introduced. It works in the third (unresolved) direction to eliminate uniform or slowly varying interfering background signals. A constant amplitude gradient pulse in the unresolved direction is applied at the same time as the usual phase encode gradient during 2D acquisition.

Toward a sustainable circular economy for cigarette butts, the most common waste worldwide on the coast.

The circular economy is based on the maximum use of resources by reducing, reusing, and recycling the elements used. Currently, the items littered most frequently in the world are cigarettes butts (CB) as these debris are freely disseminated in the marine habitat, they are generally difficult to collect and very complex to recycle. Litter CB is a great social problem that generates excessive economic costs and serious environmental problems.

Current Trends on Mechanical, Corrosion Resistance, and Antibacterial Properties of Metallic Materials.

The scope of the Special Issue entitled "Mechanical, Corrosion Resistance, and Antibacterial Properties of Metallic Materials" includes research regarding the latest developments in materials' mechanical properties and characterization, pure/applied corrosion phenomena, and advanced understanding of bacterial adhesion and the induced antibacterial properties of metallic materials [...

Water versus Oil Lubrication of Laser-Textured Ti6Al4V Alloy upon Addition of MoS Nanotubes for Green Tribology.

A Nd-YAG laser was used for texturing the Ti6Al4V surface with dimples of diameter 50 and 100 µm and centre-to-centre distance 100, 200 and 400 µm, defining the surface texture density. The tribological evaluation was conducted to analyse and compare the behaviour of un-textured and laser-textured samples under water in comparison to oil (PAO6) lubrication without and with the addition of MoS nanotubes into the lubricant. MoS nanotubes had a positive effect on friction in both media for laser-textured Ti6Al4V.

The impact of temperature on lithium toxicity in the gastropod Tritia neritea.

The most important use of lithium (Li) is in rechargeable batteries. The growing use of Li, incorrect disposal of Li-based applications, and inefficient recycling strategies for their elimination will result in the release of this metal into the aquatic systems. Alongside with the impacts caused by pollutants, organisms in coastal ecosystems are also facing environmental changes as those related with climate change scenarios, namely, seawater temperature rise.

Low-cost gradient amplifiers for small MRI systems.

We describe low-cost gradient amplifiers for small MRI systems, such as those based on small/medium permanent magnets. The requirements for MRI gradient amplifiers are quite similar to those of modestly priced audio stereo power amplifiers. Such amplifiers for sound service can be modified to be DC coupled, extending their response down to zero frequency, as needed for MRI gradient service.

Development of Mechanical, Corrosion Resistance, and Antibacterial Properties of Steels.

The total cost and environmental consequences of corrosion problems have become a major challenge to engineers [...

Effects of ocean acidification on the biochemistry, physiology and parental transfer of Ampelisca brevicornis (Costa, 1853).

Ocean acidification (OA) has received more attention in the marine research community in recent years than any other topic. Excess carbon dioxide makes the ocean more acidic, threatening marine ecosystems. There has been little research on the impact of OA on crustaceans, particularly on their physiological and potential ecosystem-level consequences.

NMR spectroscopy of coin cell batteries with metal casings.

Battery cells with metal casings are commonly considered incompatible with nuclear magnetic resonance (NMR) spectroscopy because the oscillating radio-frequency magnetic fields (“rf fields”) responsible for excitation and detection of NMR active nuclei do not penetrate metals. Here, we show that rf fields can still efficiently penetrate nonmetallic layers of coin cells with metal casings provided “ damming” configurations are avoided. With this understanding, we demonstrate noninvasive high-field in situ Li and F NMR of coin cells with metal casings using a traditional external NMR coil.

Mission impossible: Reach the carrion in a lithium pollution and marine warming scenario.

In this study we investigated the independent and synergistic effects of lithium (Li, 0.08 mM) contamination and the rising seawater temperature (21 °C; control- 15 °C) on survival and trophic interactions (foraging behaviour, success, search time, carrion preference, feeding time, and tissue consumption-the dry weight basis) of the opportunistic intertidal scavenger Tritia neritea. Trophic interactions were assessed in a two-choice test using a Y-maze design using the same amount of two carrion species (Solen marginatus and Mytilus galloprovincialis) given to all snails simultaneously.

Experimental evidence of uncertain future of the keystone ragworm Hediste diversicolor (O.F. Müller, 1776) under climate change conditions.

It is currently assumed that climate change related factors pose severe challenges to biodiversity maintenance. This paper assesses the multi-stressor effects of elevated temperature (15 °C as control, 25 °C as elevated) and CO levels (pH 8.1 as control, 7.

Precision current regulator for NMR electromagnets.

When using electromagnets or non-persistent superconducting magnets, the field stability can be directly proportional to the current stability. We present here a simple design for a current regulator based upon a high-precision, dc-dc fluxgate transformer. The output current and NMR frequency are stabilized by about a factor of 50, over times of order one hour.

Low-field magnetic resonance imaging of roots in intact clayey and silty soils.

The development of a robust method to non-invasively visualize root morphology in natural soils has been hampered by the opaque, physical, and structural properties of soils. In this work we describe a novel technology, low field magnetic resonance imaging (LF-MRI), for imaging energy sorghum ( (L.) Moench) root morphology and architecture in intact soils.

Manipulation of TiO Nanoparticle/Polymer Coatings Wettability and Friction in Different Environments.

An AISI 316L surface was functionalized by the adsorption of hydrophilic epoxy and epoxy/TiO/epoxy coatings and hydrophobic epoxy/fluoroalkylsilanefunctionalized FASTiO/epoxy coatings. We characterized the coatings' wettability, morphology and average surface roughness and discussed the influence of surface wettability and morphology on the coefficient of friction and the wear resistance. Experiments were performed in dry, distilled water and in a simulated physiological solution (Hank's solution).

NMR of petrochemical-type chemical reactions.

A simple technique is presented for NMR of chemically reacting systems at conditions of high temperature and pressure. The method can follow reactions that are typical of refinery operations - hydrogenation, transfer dehydrogenation, methanol synthesis, and isomerization. All of the reacting materials are flame-sealed into a glass capillary.

CO leakage simulation: Effects of the decreasing pH to the survival and reproduction of two crustacean species.

The effects of CO-related acidification on two crustacean populations, the isopod Cyathura carinata and the amphipod Elasmopus rapax, were studied. Three pH levels were tested: artificial seawater without CO injection and two levels of reduced pH. Even though RNA:DNA ratio was reduced for both species, no statistical significant differences were found between the control and the treatments.

RF shielding and eddy currents in NMR probes.

Shielding of the NMR sample by a thin coating of metal between the sample and the rf coil arises in some geometries. The shielding may be used for rf heating of the sample tube or for a high infrared reflectivity coating in cryoprobe applications. An important application is for a shield that prevents noise from entering the rf probe circuit while allowing pulsed magnetic field gradients or field modulation to pass.

The Influence of Surface Wettability and Topography on the Bioactivity of TiO/Epoxy Coatings on AISI 316L Stainless Steel.

Epoxy/TiO/epoxy and epoxy/FAS-TiO/epoxy coatings were applied to the surface of AISI 316L stainless steel with the aim to improve the biocompatibility and antibacterial properties. Contact-angle measurements were used to evaluate the wetting properties of the epoxy, epoxy/TiO/epoxy and epoxy/FAS-TiO/epoxy coatings. The epoxy and epoxy/TiO/epoxy coatings were hydrophilic compared with the strongly hydrophobic epoxy/FAS-TiO/epoxy coating.

Helicopter-borne NMR for detection of oil under sea-ice.

Mobile nuclear magnetic resonance (NMR) operating in Earth's magnetic field is adapted to detect leaked or spilled oil trapped in or under sea ice without the need to place any personnel on the ice. A helicopter placed a 6-meter diameter NMR coil system weighing approximately 1000 kg on 92 cm-thick ice surrogate and detected the equivalent of 1 cm thick oil under the ice surrogate in 3-1/2 min.