Multiferroic behavior in the new double-perovskite Lu2_2MnCoO6_6

We present a new member of the multiferroic oxides, Lu$_2$MnCoO$_6$, which we have investigated using X-ray diffraction, neutron diffraction, specific heat, magnetization, electric polarization, and dielectric constant measurements. This material possesses an electric polarization strongly coupled to a net magnetization below 35 K, despite the antiferromagnetic ordering of the $S = 3/2$ Mn$^{4+}$ and Co$^{2+}$ spins in an $\uparrow \uparrow \downarrow \downarrow$ configuration along the c-direction. We discuss the magnetic order in terms of a condensation of domain boundaries between $\uparrow \uparrow$ and $\downarrow \downarrow$ ferromagnetic domains, with each domain boundary producing a net electric polarization due to spatial inversion symmetry breaking. In an applied magnetic field the domain boundaries slide, controlling the size of the net magnetization, electric polarization, and magnetoelectric coupling

Effect of alloying elements on laser surface modification of powder metallurgy to improve surface mechanical properties of beta titanium alloys for biomedical application

[EN] Beta-type titanium alloy surfaces (Tie35Nbe10Ta (TNT) and Tie30Nbe4Sn (TNS)) were modified by laser using a power of 1000Wand speed of 6.7 mm/s (Condition A) and a power of 1500 W with speed of 10 mm/s (Condition B). Increasing laser conditions, the thickness of the molten layer was also increased. The initial equiaxed grains changes to quite elongated grains shape. The surfaces were structured under alfa" martensite, alfa and matrix beta. The beta phase content decreased slightly and the alfa" phase increased for both alloys increasing the laser conditions. The condition A increased the elastic modulus (E) and decreased the hardness while condition B did not affect the mechanical properties surface for the TNT system compared to base metal (BM). In TNS system the laser condition A decreased the E and increased the hardness while increasing the laser parameters (Condition B) both E and hardness decreased compared to BM. The laser surface treatment was influenced by the levels of alloying elements present promoting most significant changes in the microstructure and mechanical properties in the TNS system.This work was supported by the Ministerio Espan~ol de Ciencia, Innovaci?on y Universidades, Spain with Grant RTI2018-097810-B-I00, RTI2018-096472-B-I00 and the European Union (EU) through Fondo Europeo de Desarrollo Regional (FEDER) , Spain.Rossi, MC.; Amado, JM.; Tobar, MJ.; Vicente-Escuder, Á.; Yáñez, A.; Amigó, V. (2021). Effect of alloying elements on laser surface modification of powder metallurgy to improve surface mechanical properties of beta titanium alloys for biomedical application. Journal of Materials Research and Technology. 14:1222-1234. https://doi.org/10.1016/j.jmrt.2021.07.037122212341

Preliminary study on the use of the 137 Cs method for soil erosion investigation in the pampean region of Argentina

Soil erosion is the most important degradation process in A rgentine. According to the estimation of 4.9 millon ha in Pampa Ondulada Region, 1.600.000 ha (36% of agricultural soils) are affected by the erosion. Field measurements of soil erosion and sediment deposition using classical techniques are difficult, time consuming, and expensive but indispensable to feed the prediction models for conservation practices design and fa rm planning. Many authors have reported that the measurement of fallout nuclides is useful tool to characterize geomorphical processes. Walling and He proposes models for conve rting 137Cs depletion/enrichment amounts to net soil loss/deposition. These models are based in the comparison between a reference 137Cs profile in a long term undisturbed site (control site) and the 137Cs profiles in the suspected eroded or deposited sites in the landscape. The aim of this study is to provide a complete and well representative set of data on the erosion intensity in topographical conditions for the Pampa Ondulada Region in A rgentine by using a tracer technique. The study area is a small watershed (about 300 ha), located in Arroyo del Tala medium basin, within Partido of San Pedro in Buenos Aires Province, Argentine. This paper presents a group of results from a detailed investigation of erosion and sediment delivery, within a 49 ha cultivated field study site in this watershed. The base of sampling strategy is the grid approach. A reference inventory, representing the local fallout input, was searched for at a site experiencing neither erosion nor deposition. Radiocaesium analyses were made at the Nuclear Regulatory Authority Laboratory by a GE Hp detector. To make an interpretation of 137Cs distribution of soil losses and sedimentation, the Mass Balance Model 2 was used (Walling and He 1997). The erosion/deposition rates from Mass Balance Model 2 are in the range of 0 to -30 t·ha-1·y-1 for erosion, and 0 to 19 t·ha-1·y-1 for deposition, and these values matched well, with the rates of erosion obtained by classical methods. The 137Cs spatial and depth distribution are showed in a map, and enabled to study the relationship of the erosion to the topography, and a good discrimination in subclasses within moderate erosion class and sedimentation class

Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments

Methyl ethyl ketone (MEK) enters the atmosphere following direct emission from vegetation and anthropogenic activities, as well as being produced by the gas-phase oxidation of volatile organic compounds (VOCs) such as n-butane. This study presents the first overview of ambient MEK measurements at six different locations, characteristic of forested, urban and marine environments. In order to understand better the occurrence and behaviour of MEK in the atmosphere, we analyse diel cycles of MEK mixing ratios, vertical profiles, ecosystem flux data, and HYSPLIT back trajectories, and compare with co-measured VOCs. MEK measurements were primarily conducted with proton-transfer-reaction mass spectrometer (PTR-MS) instruments. Results from the sites under biogenic influence demonstrate that vegetation is an important source of MEK. The diel cycle of MEK follows that of ambient temperature and the forest structure plays an important role in air mixing. At such sites, a high correlation of MEK with acetone was observed (e.g. r2 = 0.96 for the SMEAR Estonia site in a remote hemiboreal forest in Tartumaa, Estonia, and r2 = 0.89 at the ATTO pristine tropical rainforest site in central Amazonia). Under polluted conditions, we observed strongly enhanced MEK mixing ratios. Overall, the MEK mixing ratios and flux data presented here indicate that both biogenic and anthropogenic sources contribute to its occurrence in the global atmosphere

Effect of Alloying Elements on Laser Surface Modification of Powder Metallurgy to Improve Surface Mechanical Properties of Beta Titanium Alloys for Biomedical Application

[Abstract] Beta-type titanium alloy surfaces (Tie35Nbe10Ta (TNT) and Tie30Nbe4Sn (TNS)) weremodified by laser using a power of 1000 W and speed of 6.7 mm/s (Condition A) and a powerof 1500 W with speed of 10 mm/s (Condition B). Increasing laser conditions, the thicknessof the molten layer was also increased. The initial equiaxed grains changes to quiteelongated grains shape. The surfaces were structured undera00martensite,aand matrixb.Thebphase content decreased slightly and thea00phase increased for both alloysincreasing the laser conditions. The condition A increased the elastic modulus (E) anddecreased the hardness while condition B did not affect the mechanical properties surfacefor the TNT system compared to base metal (BM). In TNS system the laser condition Adecreased the E and increased the hardness while increasing the laser parameters (Con-dition B) both E and hardness decreased compared to BM. The laser surface treatment wasinfluenced by the levels of alloying elements present promoting most significant changesin the microstructure and mechanical properties in the TNS systemThis work was supported by the Ministerio Español de Ciencia, Innovación y Universidades, Spain with Grant RTI2018-097810-B-I00, RTI2018-096472-B-I00 and the European Union (EU) through Fondo Europeo de Desarrollo Regional (FEDER), Spai

Updating temperature and salinity mean values and trends in the Western Mediterranean: the RADMED project

Postprin

Influencia de los parámetros nutricionalesen cirugía de cadera

Bajo la hipótesis de que los parámetros nutricionales influyen en el desarrollo perioperatorio de la cirugía de cadera realizamos un estudio prospectivo observacional de tipo clínico sobre 100 pacientes con una edad media de 76 años. Realizamos una evaluación clínica al ingreso: talla, peso, pliegue cutáneo, circunferencia braquial y muscular. Medición de proteínas plasmáticas y linfocitos totales al ingreso, en el postoperatorio y cada 7 días. Definimos los pacientes según los valores nutricionales analíticos y clínicos. El 51% de nuestros pacientes presentaban desnutrición caloricoproteica. La media transfusional en malnutridos fue 600 c.c. frente a 350 c.c. del grupo nutrido (p < 0,05). El 73% de las complicaciones se presentaron en pacientes malnutridos. No hallamos diferencias en los períodos de sedestación y deambulación, aunque sí en la estancia hospitalaria, 15 días frente a 18,5 días (p < 0,01). La prealbúmina mostró variaciones de forma más precoz ante el acto quirúrgico.A prospective observation was conducted with the hypothesis that the nutritional situation has influence in postoperative development of hip surgery [n = 100; age 76 years (55-95)]. A nutritional evaluation was performed before surgery through the evolution of height, body weight, skin fold and braquial and muscular circunference. Serie proteins and lymphocytes levels were measured during hospital admission, in postoperative and each seven days. A 51% of patients showed protein-energy malnutrition (PEM). Transfusional haematic requirements were 600 c c . in malnutrition patients and 350 c.c. in the rest (p < 0.05). Complications appeared in PEM patients in 73% cases. The hospital stay was longer in those patients who presented PEM upon admittance (p < 0.01). Postoperatively, the prealbumin was the protein whose serie level had faster changes

Exploiting the potential of bioactive molecules extracted by ultrasounds from avocado peelsfood and nutraceutical applications

Natural bioactive compounds from food waste have fomented interest in food and pharmaceutical industries for the past decade. In this work, it purposed the recovery of bioactive avocado peel extract using an environmentally friendly technique: the ultrasound assisted extraction. The response surface methodology was applied in order to optimize the conditions of the extraction, ethanol-water mixtures and time. The optimized extracts (ethanol 38.46%, 44.06 min, and 50 °C) were chemically characterized by HPLC-ESI-MS and FTIR. Its antioxidant ability, as well as, its effect on cell metabolic activity of normal (L929) and cancer (Caco-2, A549 and HeLa) cell lines were assessed. Aqueous ethanol extracts presented a high content in bioactive compounds with high antioxidant potential. The most representative class of the phenolic compounds found in the avocado peel extract were phenolic acids, such as hydroxybenzoic and hydroxycinnamic acids. Another important chemical group detected were the flavonoids, such as flavanols, flavanonols, flavones, flavanones and chalcone, phenylethanoids and lignans. In terms of its influence on the metabolic activity of normal and cancer cell lines, the extract does not significantly affect normal cells. On the other hand, it can negatively affect cancer cells, particularly HeLa cells. These results clearly demonstrated that ultrasound is a sustainable extraction technique, resulting in extracts with low toxicity in normal cells and with potential application in food, pharmaceutical or nutraceutical sectors.The authors acknowledge the financial support received from “Xunta de Galicia” (GRC ED431C 2017/62-GRC, and Project ED431F 2020/03). These projects are partially funded by the FEDER Program of the European Union (“Unha maneira de facer Europa”). This research was also funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit. Beatriz Gullón would like to express her gratitude to the Spanish Ministry of Economy and Competitiveness for her postdoctoral grant (Reference RYC2018-026177-I).info:eu-repo/semantics/publishedVersio