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

Charge ordering and dielectric properties in the near half-doped Pr0.79Na0.21MnO3 perovskite

[Abstract] The Pr0.79Na0.21MnO3 perovskite has been prepared in polycrystalline form by a ceramic method. We have carried out its structural characterization by synchrotron X-ray powder diffraction (SXRPD) at room temperature and at 150 K (T<TCO). In the charge ordering (CO) state, the SXRPD data can be refined both on the basis of the site-centred model and the bond-centred model proposed for half-doped manganites, without a clear advantage of one model over the other. From the dielectric point of view, at the CO temperature this manganite shows a maximum in the dielectric constant whose origin is intrinsic, and cannot be attributed to the presence of extrinsic factors. We relate this dielectric behaviour to the formation of polar entities at the temperature of charge condensation, due to an asymmetric charge distribution intermediate between site-centred and bond-centred type.Xunta de Galicia; PGIDIT06PXB103298PRMinisterio de Educación y Ciencia; Project FEDER MAT 2004-0513

A Cremophor-Free Formulation for Tanespimycin (17-AAG) using PEO-b-PDLLA Micelles: Characterization and Pharmacokinetics in Rats

Tanespimycin (17-allylamino-17-demethoxygeldanamycin or 17-AAG) is a promising heat shock protein 90 inhibitor currently undergoing clinical trials for the treatment of cancer. Despite its selective mechanism of action on cancer cells, 17-AAG faces challenging issues due to its poor aqueous solubility, requiring formulation with Cremophor EL (CrEL) or ethanol (EtOH). Therefore, a CrEL-free formulation of 17-AAG was prepared using amphiphilic diblock micelles of poly(ethylene oxide)-b-poly(D,L-lactide) (PEO-b-PDLLA). Dynamic light scattering revealed PEO-b-PDLLA (12:6 kDa) micelles with average sizes of 257 nm and critical micelle concentrations of 350 nM, solubilizing up to 1.5 mg/mL of 17-AAG. The area under the curve (AUC) of PEO-b-PDLLA micelles was 1.3-fold that of the standard formulation. The renal clearance (CLrenal) increased and the hepatic clearance (CLhepatic) decreased with the micelle formulation, as compared to the standard vehicle. The micellar formulation showed a 1.3-fold increase in the half-life (t1/2) of the drug in serum and 1.2-fold increase in t1/2 of urine. As expected, because it circulated longer in the blood, we also observed a 1.7-fold increase in the volume of distribution (Vd) with this micelle formulation compared to the standard formulation. Overall, the new formulation of 17-AAG in PEO-b-PDLLA (12:6 kDa) micelles resulted in a favorable 150-fold increase in solubility over 17-AAG alone, while retaining similar properties to the standard formulation. Our data indicates that the nanocarrier system can retain the pharmacokinetic disposition of 17-AAG without the need for toxic agents such as CrEL and EtOH

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

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

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

Laparoscopic surgery of vesicovaginal fistula: results of a multi institutional experience

Indexación: Web of Science; Scielo.Introduction: Vesico-vaginal fistula is a rare complication of gynecologic surgery, with a high rate of surgical resolution O'Conor open technique. Aim: To report the results of a multi-institutional experience in laparoscopic repair of vesico-vaginal fistula. Material and Methods: Between January 2006 and June 2011, 21 laparoscopic vesico-vaginal fistula were performed. The surgical technique, demographic variables and results are described. Results: The mean age was 45.6 years. The average time between the diagnosis of the fistula and the laparoscopic repair was 15.23 months. The mean total operative time (bladder and laparoscopic) was 153.12 minutes and the average hospital stay was 2.7 days. The average time of bladder catheter was 9.4 days. There was a minimal recurrence of a fistula, repaired by a vaginal approach. Urethrocystography revealed indemnity of the repair in the other 20 cases. The overall success rate was 95.2% (20 out of 21 patients) Conclusions: The laparoscopic approach follows all principles for repair of a vesico-vaginal fistulas. It look like a good alternative in the hands of experienced surgeons. Key words: Vesicovaginal fistula, hysterectomy, complications, laparoscopy, O'Conor.Introducción: La fístula vesico-vaginal es una complicación infrecuente de la cirugía ginecológica, con alta tasa de resolución quirúrgica con la técnica abierta tradicional de O'Conor. Objetivo: Comunicar los resultados de una experiencia multi-institucional en la reparación laparoscópica de las fístulas vesico-vaginales. Material y Método: Entre enero de 2006 y junio de 2011 se realizaron 21 reparaciones de fístulas vesico-vaginales por vía laparoscópica. Se describe la técnica quirúrgica y se analizan las variables demográficas, quirúrgicas y resultados de la serie. Resultados: La edad media de las pacientes fue de 45,6 años. El tiempo promedio transcurrido entre el diagnóstico de la fistula y su reparación laparoscópica fue de 15,23 meses. El tiempo quirúrgico medio total (vesical y laparoscópico) fue de 153,12 min y el de hospitalización 2,7 días. El tiempo promedio de catéter uretro-vesical fue de 9,4 días. Hubo una mínima recidiva de una fístula, la cual fue reparada por vía vaginal. El control radiológico mediante cistografía reveló indemnidad de la reparación en el resto de los casos. La tasa global de éxito fue de 95,2% (20 de 21 pacientes) Conclusiones: El abordaje laparoscópico permite cumplir con todos los principios para la reparación de las fístulas vesico-vaginales. La reducción de la morbilidad y la eficacia del procedimiento, lo transforman en una excelente alternativa en manos de cirujanos experimentados. Palabras clave: Fístula vesico-vaginal, histerectomía, complicaciones, laparoscopia, O'Conor.http://ref.scielo.org/f3vxt

Customized Smart Andon System to Improve the Efficiency of Industrial Departments

35-37A customized industrial system to realize the supporting requests in manufacturing lines with detailed statistical information is presented. Also called customized smart Andon system. The system is based on a software and hardware design customized for particular industry needs according to the internal organizational structure. The results of the projection are that Andon system permits an important reduction of the time required for attending and finishing whatever problem in the manufacturing line

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