Encapsulation of gold nanostructures and oil-in-water nanocarriers in microgels with biomedical potential

Indexación: Scopus.Funding: This research was funded by FONDECYT 1161450, 1150744, 11130494 and 1170929, FONDEQUIP EQM160157, EQM170111, CONICYT-FONDAP 15130011, and CONICYT PhD Scholarship 21141137.Here we report the incorporation of gold nanostructures (nanospheres or nanorods, functionalized with carboxylate-end PEG) and curcumin oil-in-water (O/W) nanoemulsions (CurNem) into alginate microgels using the dripping technique. While gold nanostructures are promising nanomaterials for photothermal therapy applications, CurNem possess important pharmacological activities as reported here. In this sense, we evaluated the effect of CurNem on cell viability of both cancerous and non-cancerous cell lines (AGS and HEK293T, respectively), demonstrating preferential toxicity in cancer cells and safety for the non-cancerous cells. After incorporating gold nanostructures and CurNem together into the microgels, microstructures with diameters of 220 and 540 µm were obtained. When stimulating microgels with a laser, the plasmon effect promoted a significant rise in the temperature of the medium; the temperature increase was higher for those containing gold nanorods (11–12 ◦ C) than nanospheres (1–2 ◦ C). Interestingly, the incorporation of both nanosystems in the microgels maintains the photothermal properties of the gold nanostructures unmodified and retains with high efficiency the curcumin nanocarriers. We conclude that these results will be of interest to design hydrogel formulations with therapeutic applications. © 2018 by the authors.https://www.mdpi.com/1420-3049/23/5/120

Geoquímica de los procesos de alteración hidrotermal en la mineralización de Sb de Mari Rosa (zona Centro Ibérica)

The Central Iberian Zone of the Hesperian Massif hosts a series of late Hercynian veintype Sb deposits. One of them is the Mari Rosa mineralization, hosted by metagreywackes and slates belonging to the so-called Schist-Greywacke Complex (Upper Precambrian). The mineralization is characterized by a complex paragenesis comprising arsenopyrite-(pyrite), stibnite-gold and pyrite-pyrrhotite-galena-sphalerite-chalcopyrite-tetrahedrite-boulangeritestibnite. Of these only the second episode was of importance and gave rise to the main mineralized bodies of the deposito Two types of veins can be defined in Mari Rosa: Vp, showing pinch and swell structures parallel to the main foliation planes (S2), and Vo, massive lensoid-shaped bodies of gold bearing stibnite postdating the Vp veins and cross-cutting S2. Hydrothermal alteration consists oí a mild sericitization, chloritization and carbonatization oí the metasedimentary rocks around the veins. Due to the mineralogy oí the hostrocks (muscovite, chlorite, quartz), these alteration facies are not easily recognizable. However, the study of chemical changes around the veins allow a clear characterization of the hydrotermal processes. !hus, a remarkable increase in the ratio K2O/Na2O (from 1.2 in the regional rocks to 5.1 lfi the Vp contact rocks) and a decrease in the ratio SiO2/volatiles (írom 27.4 in the regional rocks to 13.5 in the Vp contact rocks) can be used as clear-cut indicators of the extension and magnitude of the hydrothermal alteration. Other changes included increases lfi. Sb (between 5,000 and 10,000 times the regional background), Mo (up to 60 times the regional background) and Au (values oí up to 32 ppm) around the veins. Besides, a high positive correlation between Sb and Mo is observed (R = 1 in the veins and R = 0.9 in the host rocks). The isotopic signature of stibnite and pyrite (average δ34S of 0.3‰ and -3.9‰, respectively) is close to the typical values of magmatic sulphur. This, together with the high correlations between Sb and Mo strongly suggest a genetic relationship between the Mari Rosa mineralization and the intrusion of the Alburquerque batholith.La zona Centro Ibérica del Macizo Hespérico contiene una serie de depósitos filonianos de antimonio de edad tardihercínica. Uno de ellos es la mineralización de Mari Rosa, encajada en metagrauvacas y pizarras pertenecientes al Complejo Esquisto Grauváquico (Precámbrico Superior) y situada en las proximidades del batolito de Alburquerque (Westfaliense/ Estefaniense). La mineralización está caracterizada por una paragénesis compleja que incluye arsenopirita-(pirita), estibina-oro y pirita-pirrotina-galena-esfalerita-calcopirita-tetraedrita- boulangerita-estibina. De éstos, sólo el segundo episodio fue importante y dio lugar a los principales cuerpos mineralizados del depósito. Dos tipos de venas pueden definirse en Mari Rosa: Vp, mostrando estructuras abudinadas paralelas a la esquistosidad principal (S2/), y Yo, bolsadas lenticulares de estibina masiva aurífera posteriores a Vp y cortando a S2/. La alteración hidrotermal consiste en una débil sericitización, cloritización y carbonatización de las rocas metasedimentarias en torno a las venas. Debido a la mineralogía de estas rocas (moscovita, clorita, cuarzo), estas facies de alteración no se reconocen fácilmente. Sin embargo, el estudio de los cambios químicos alrededor de las venas permite una caracterización adecuada de los procesos hidrotermales. Así, un notable incremento en la razón K2O/Na2O (desde 1,2 en las rocas regionales a 5,1 en la proximidad de las venas Vp) y un descenso en SiO2/volátiles (desde 27,4 en las rocas regionales a 13,5 en la proximidad de las venas Vp) pueden ser utilizados como marcadores de la magnitud y extensión de la alteración hidrotermal. Otros cambios incluyen importantes incrementos en Sb (valores entre 5.000 y 10.000 veces la media regional), Mo (hasta 60 veces su concentración regional) y Au (con valores máximos de hasta 32 ppm) en torno a las venas. Por otra parte, se observa una elevada correlación positiva entre Sb y Mo (R = 1 en las venas mineralizadas, R = 0,9 en las rocas encajantes). La composición isotópica media de estibina y pirita δ34S = 0,3 ‰ y-3,9 ‰, respectivamente) presenta valores próximos a los de azufre de origen magmático. Esto, junto con las significativas correlaciones entre Sb y Mo permiten sugerir una relación genética entre la mineralización de Mari Rosa y la intrusión del batolito de Alburquerque

Evidence for spin to charge conversion in GeTe(111)

GeTe has been predicted to be the father compound of a new class of multifunctional materials, ferroelectric Rashba semiconductors, displaying a coupling between spin-dependent k-splitting and ferroelectricity. In this paper, we report on epitaxial Fe/GeTe(111) heterostructures grown by molecular beam epitaxy. Spin-pumping experiments have been performed in a radio-frequency cavity by pumping a spin current from the Fe layer into GeTe at the Fe ferromagnetic resonance and detecting the transverse charge current originated in the slab due to spin-to-charge conversion. Preliminary experiments indicate that a clear spin to charge conversion exists, thus unveiling the potential of GeTe for spin-orbitronics

Burdigalian deposits of the Santa Cruz formation in the Sierra Baguales, austral (magallanes) basin: Age, depositional environment and vertebrate fossils

A succession of marine and continental strata on the southern flank of Cerro Cono in the Sierra Baguales, northeast of Torres del Paine, can be correlated with stratigraphic units exposed along the southern border of the Lago Argentino region in Santa Cr

A comparative evaluation of dried activated sludge and mixed dried activated sludge with rice husk silica to remove hydrogen sulfide.

The aim of this study was to investigate the effectiveness of dried activated sludge (DAS) and mixed dried activated sludge with rice husk silica (DAS & RHS) for removal of hydrogen sulfide (H2S). Two laboratory-scale filter columns (packed one litter) were operated. Both systems were operated under different conditions of two parameters, namely different inlet gas concentrations and different inlet flow rates. The DAS & RHS packed filter showed more than 99.96% removal efficiency (RE) with empty bed residence time (EBRT) of 45 to 90 s and 300 mg/L inlet concentration of H2S. However, the RE decreased to 96.87% with the EBRT of 30 s. In the same condition, the DAS packed filter showed 99.37% RE. Nonetheless, the RE was shown to have dropped to 82.09% with the EBRT of 30 s. The maximum elimination capacity (EC) was obtained in the DAS & RHS packed filter up to 52.32 g/m3h, with the RE of 96.87% and H2S mass loading rate of 54 g/m3h. The maximum EC in the DAS packed filter was obtained up to 44.33 g/m3h with the RE of 82.09% and the H2S mass loading rate of 54 g/m3h. After 53 days of operating time and 54 g/m3h of loading rates, the maximum pressure drop reached to 3.0 and 8.0 (mm H2O) for the DAS & RHS packed and DAS packed filters, respectively. Based on the findings of this study, the DAS & RHS could be considered as a more suitable packing material to remove H2S

Spin-pumping into surface states of topological insulator {\alpha}-Sn, spin to charge conversion at room temperature

We present experimental results on the conversion of a spin current into a charge current by spin pumping into the Dirac cone with helical spin polarization of the elemental topological insulator (TI) {\alpha}-Sn[1-3]. By angle-resolved photoelectron spectroscopy (ARPES) we first confirm that the Dirac cone at the surface of {\alpha}-Sn (0 0 1) layers subsists after covering with Ag. Then we show that resonant spin pumping at room temperature from Fe through Ag into {\alpha}-Sn layers induces a lateral charge current that can be ascribed to the Inverse Edelstein Effect[4-5]. Our observation of an Inverse Edelstein Effect length[5-6] much longer than for Rashba interfaces[5-10] demonstrates the potential of the TI for conversion between spin and charge in spintronic devices. By comparing our results with data on the relaxation time of TI free surface states from time-resolved ARPES, we can anticipate the ultimate potential of TI for spin to charge conversion and the conditions to reach it.Comment: 14 pages, 5 figure

Efecto agudo de ejercicio isométrico sobre parámetros autonómicos en adultos sedentarios obesos y con sobrepeso

Introduction: Obesity is understood as a chronic inflammation associated with complications in the autonomic nervous system dysfunction related to cardiovascular diseases. And isometric exercise, represented by manual grip strength, favors the reduction of cardiovascular risk and autonomic imbalance. Objective: to describe the acute response of an isometric exercise (IE) compared to the effect of an aerobic exercise (AE), analyzing the autonomic parameters of heart rate variability (LF/HF), diastolic blood pressure (DBP), systolic blood pressure (SBP) and heart rate (HR) in obese and overweight people. Methodology: 20 participants were randomly distributed into 2 groups; those who performed an aerobic exercise session on a cycle ergometer for 15 min at 50 watts (n=10) and those who performed an IE session at 30% of maximal strength (n=10). Both were evaluated pre and post intervention, the variables were analyzed using the Mann-Whitney U statistical test with a significance level of p<0.05. Results: IE produced statistically significant changes in SBP (p= 0.001), LH/HF (p=0.02) and HR (p=0.018), while DBP improved, but not significantly. Conclusions: an EI session generates a greater decrease than EA in HRV, HR and SBP variables.Introducción: La obesidad es entendida como una inflamación crónica asociada a complicaciones en la disfunción del sistema nervioso autónomo relacionada con enfermedades cardiovasculares. Y el ejercicio isométrico, representado por la fuerza de prensión manual, favorece la reducción del riesgo cardiovascular y al desequilibrio autonómico. Objetivo: describir la respuesta aguda de un ejercicio isométrico (EI) comparándolo con el efecto de un ejercicio aeróbico (EA), analizando los parámetros autonómicos de variabilidad de la frecuencia cardiaca (LF/HF), presión arterial diastólica (PAD), sistólica (PAS) y la frecuencia cardiaca (FC) en personas obesos y en sobrepeso. Metodología: 20 participantes fueron distribuidos al azar en 2 grupos; los que realizaron una sesión de ejercicio aeróbico en cicloergómetro durante 15 min a 50 watts (n=10) y los que realizaron una sesión de EI al 30% de la fuerza máxima. Ambos fueron evaluados pre y post intervención, se analizaron las variables mediante la prueba estadística U de Mann-Whitney con un nivel de significancia p<0,05. Resultados: El EI produjo cambios estadísticamente significativos en PAS (p= 0,001), LH/HF (p = 0,02) y FC (p=0,01), mientras que la PAD mejoró, pero no de forma significativa. Conclusiones: una sesión de EI, genera una mayor disminución que el EA en las variables de VFC, FC y PAS

Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of s√=7TeV proton-proton collisions

Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson