Efficacy of DOPE/DC-cholesterol liposomes and GCPQ micelles as AZD6244 nanocarriers in a 3D colorectal cancer in vitro model

Aim: In this work, we use cationic organic nanocarriers as chemotherapy delivery platforms and test them in a colorectal cancer 3D in vitro model. Materials & methods: We used 3beta-(N-[N′,N′-dimethylaminoethane]carbamoyl])cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) liposomes and N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) micelles, to deliver AZD6244, a MEK inhibitor, to HCT116 cells cultured as monolayers and in 3D in vitro cancer models (tumoroids). Results: Nanoparticle-mediated drug delivery was superior to the free drug in monolayer experiments and despite their therapeutic effect being hindered by poor diffusion through the cancer mass, GCPQ micelles were also superior in tumoroids. Conclusion: These results support the role of nanoparticles in improving drug delivery and highlight the need to include 3D cancer models in early phases of drug development

Efficacy of DOPE/DC-cholesterol liposomes and GCPQ micelles as AZD6244 nanocarriers in a 3D colorectal cancer in vitro model

AIM: In this work, we use cationic organic nanocarriers as chemotherapy delivery platforms and test them in a colorectal cancer 3D in vitro model. MATERIALS & METHODS: We used 3beta-(N-[N',N'-dimethylaminoethane]carbamoyl])cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) liposomes and N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) micelles, to deliver AZD6244, a MEK inhibitor, to HCT116 cells cultured as monolayers and in 3D in vitro cancer models (tumoroids). RESULTS: Nanoparticle-mediated drug delivery was superior to the free drug in monolayer experiments and despite their therapeutic effect being hindered by poor diffusion through the cancer mass, GCPQ micelles were also superior in tumoroids. CONCLUSION: These results support the role of nanoparticles in improving drug delivery and highlight the need to include 3D cancer models in early phases of drug development

Electron-correlation effects in appearance-potential spectra of Ni

Spin-resolved and temperature-dependent appearance-potential spectra of ferromagnetic Nickel are measured and analyzed theoretically. The Lander self-convolution model which relates the line shape to the unoccupied part of the local density of states turns out to be insufficient. Electron correlations and orbitally resolved transition-matrix elements are shown to be essential for a quantitative agreement between experiment and theory.Comment: LaTeX, 6 pages, 2 eps figures included, Phys. Rev. B (in press

Can serious games help to mitigate climate change? Exploring their influence on Spanish and American teenagers’ attitudes

Es urgente y necesario reducir las emisiones de gases de efecto invernadero y mitigar el cambio climático, y esta lucha requiere un cambio en las actitudes de los adolescentes. En la búsqueda de nuevos enfoques dirigidos a los jóvenes, los serious games en formato online parecen una prometedora herramienta de comunicación y educación. Basándonos en el juego 2020 Energy como estudio de caso, el principal objetivo de este artículo es examinar la influencia de dicho juego sobre las actitudes de adolescentes españoles y estadounidenses (N = 108), empleando un diseño pretest-posttest con una condición experimental (jugar al juego) y una condición de control (no jugar al juego). Los resultados muestran que no había diferencias estadísticamente significativas después de jugar al juego, aunque una observación más detallada de cada factor ofrece algunas consecuencias positivas.There is an urgent need to curb emissions and mitigate climate change, and this fight requires a change in teenagers’ attitudes. In search of new approaches targeting youth, online games are seen as a promising tool for communication and education. Using the serious game 2020 Energy as a case study, the main objective of this paper is to examine the influence of the game on Spanish and American teenagers’ attitudes (N = 108), employing a pretest-posttest design with an experimental condition (playing the game) and a control condition (not playing the game). Results show that there have not been statistically significant differences after playing the game, although when looking closer at each factor, some positive consequences can be found.HUM466 Acceso y evaluación de la información científic

Optically induced forces and torques:Interactions between nanoparticles in a laser beam

Distinctive optical forces and torques arise between nanoparticles irradiated by intense laser radiation. These forces, associated with a pairwise process of stimulated scattering, prove to enable the possibility of producing significant modifications to both the form and magnitude of interparticle forces, with additional contributions arising in the case of dipolar materials. Moreover, such forces have the capacity to generate unusual patterns of nanoscale response, entirely controlled by the input beam characteristics- principally the optical frequency, intensity, and polarization. Based on quantum electrodynamical theory, a general result is secured for the laser-induced force under arbitrary conditions, incorporating both static and dynamic coupling mechanisms. Specific features of the results are identified for pairs of particles with prolate cylindrical symmetry, e.g., carbon nanotubes, where it is shown that the laser-induced forces and torques are sensitive functions of the pair spacing and orientation, and the laser beam geometry; significantly, they can be either repulsive or attractive according to conditions. For nanoparticles trapped in a Laguerre-Gaussian laser beam the results also reveal additional and highly distinctive torques that suggest further possibilities for nanomanipulation with light. The paper concludes with a discussion on several potential applications of such forces. © 2005 The American Physical Society

Photon-Graviton Amplitudes from the Effective Action

We report on the status of an ongoing effort to calculate the complete one-loop low-energy effective actions in Einstein-Maxwell theory with a massive scalar or spinor loop, and to use them for obtaining the explicit form of the corresponding M-graviton/N-photon amplitudes. We present explicit results for the effective actions at the one-graviton four-photon level, and for the amplitudes at the one-graviton two-photon level. As expected on general grounds, these amplitudes relate in a simple way to the corresponding four-photon amplitudes. We also derive the gravitational Ward identity for the 1PI one-graviton -- N photon amplitude.Comment: 9 pages, 2 figures, talk given by C. Schubert at "Supersymmetries and Quantum Symmetries - SQS`2011", JINR Dubna, July 18 - 23, 2011 (to appear in the Proceedings

Curie temperature enhancement of electron doped Sr2_2FeMoO6_6 perovskites studied by photoemission spectroscopy

We report here on the electronic structure of electron-doped half-metallic ferromagnetic perovskites such Sr$_{2-x}$La$_x$FeMoO$_6$ ($x$=0-0.6) as obtained from high-resolved valence-band photoemission spectroscopy (PES). By comparing the PES spectra with band structure calculations, a distinctive peak at the Fermi level (E$_F$) with predominantly (Fe+Mo) t$_{2g}^\downarrow$ character has been evidenced for all samples, irrespectively of the $x$ values investigated. Moreover, we show that the electron doping due to the La substitution provides selectively delocalized carriers to the t$_{2g}^\downarrow$ metallic spin channel. Consequently, a gradual rising of the density of states at the E$_F$ has been observed as a function of the La doping. By changing the incoming photon energy we have shown that electron doping mainly rises the density of states of Mo parentage. These findings provide fundamental clues for understanding the origin of ferromagnetism in these oxides and shall be of relevance for tailoring oxides having still higher T$_C$

RESISTENCIA A LA FRACTURA DE PREMOLARES TRATADOS ENDODÓNTICAMENTE, RESTAURADOS CON DOS SISTEMAS DE PERNOS Y NÚCLEO

Objetivos: Medir la resistencia a la fractura en premolares tratados endodónticamente, restaurados condos sistemas de pernos (Colados/ Prefabricados) y analizar el patrón de fractura que se produce en laraíces. Materiales y Métodos: a 60 premolares humanos monorradiculares se les realizó la terapiaendodóntica. Se dividió la muestra aleatoriamente en dos grupos (30 c/u), el grupo 1 (G1FV) se restaurócon pernos prefabricados de Fibra de Vidrio (Ángelus®) y el grupo 2 (G2C) con pernos colados dealeación base (Orca Plus /Ventura), utilizando cemento resinoso Nexus 2 (Kerr), los 2/3 coronales deambos grupos fueron restaurados con resina compuesta híbrida (Glacier A1/ SDI). Las muestras fueroncargadas a una velocidad de 2mm/min y a una angulación de 30° con el eje longitudinal del diente en lamáquina de prueba universal (Shimadzu AGS- J), la resistencia a la fractura fue medida en newtons yanalizada con ANOVA de una vía; por medio de la observación directa y Rx se determinó el patrón defractura que fue analizado con X² y Prueba Z. Resultados: En relación a resistencia a la fractura no hubodiferencia estadísticamente significativa entre los grupos (p=0,741). En cuanto al patrón de fractura seobservó diferencia estadísticamente significativa entre los grupos estudiados (Zc=4,47). Conclusiones:En las condiciones en las que se realizó esta investigación se observó que los dos sistemas de perno ynúcleo resisten de manera similar a las tensiones inducidas. En cuanto al patrón de fractura radicular enel G1FV se producen menor número de fracturas no reparables cuando se compararon con el G2C.Fracture resistance in endodontically treated premolars restored with two systems of posts.Summary:Objective: The purpose of this research was to compare the fracture resistance of human premolarsrestored with prefabricated fiber glass posts and custom cast post and to analyze the nature of the rootfracture patterns. Methods: 60 human monoradicular premolars were prepared with endodontic therapyand randomly assigned to one of two groups: group 1 (G1FV) recovered with prefabricated fiber glassposts (Ángelus) or group 2 (G2C) with custom cast base alloy posts (Orca /Ventura Extra) using resinousluting cement (Nexus2/Kerr). 2/3 of the crowns were restored with hybrid composite (Glacier A1/SDI).The samples were loaded at a speed of 2mm/min and to a 30° angulation with the longitudinal axis of thetooth in the universal testing machine (Shimadzu AGS- J).The fracture resistance was recorded andanalyzed with one way ANOVA. The nature of the root fracture patterns was determined through directobservation and Rx; these data were analyzed with X² and Z test. Results: After the ANOVA analysis nostatistically significant differences were observed in relation to fracture resistance between groups (p =0,741). However, significant differences were found for the nature of the root fracture between thegroups (Zc=4, 47). Conclusions: Under the conditions of this study, both systems of posts have asimilar fracture resistance. In relation to root fracture patterns, there are less catastrophic fractures inthe G1FV when compared to G2C

Evaluación de la calidad fisicoquímica de jitomate (Lycopersicum esculentum Mill), tipo saladette Variedad El Cid F-1

El experimento se realizó con el fin de determinar algunas de las características fisicoquímicas bajo diversos grados de madurez, seleccionándolos de acuerdo con su porcentaje de coloración; peso, dimensiones, pH, °Brix y acidez titulable las cuales son parámetros para decidir si el fruto está comprendido en los estándares de calidad que exige el mercado mayorista, así como relacionar tales características con respecto a la nutrición que se le utilizó. De esta manera se determinaran los cambios en la calidad de las frutas de jitomate en sus diversos estados de madurez en que fueron cosechados. El objetivo del trabajo fue “Evaluar la calidad del cultivo de jitomate (Lycopersicum esculentum Mill) en cada uno de sus seis grados de maduración”. Los resultados nos muestran que los estados más tempranos de maduración presentaron los valores más altos para la variable ancho del fruto. (6.5306, 6.3360 y 6.0162 respectivamente), Con respecto al largo del fruto el análisis estadístico nos muestra que el grado rojo claro presentó el rango más grande de diámetro polar., mientras que el quebrado adquirió el menor valor, aunque no se presentó diferencia significativa entre tratamientos. El color rojo claro fué el de mayor peso con respecto a los demás grados mientras que el color quebrado fue precisamente lo contrario

Evaluación de la calidad edafológica y toxicológica de tres invernaderos con producción de hortalizas

El objetivo de esta investigación fue determinar la calidad edafológica y toxicológica de tres de los invernaderos de la Facultad de Ciencias Biológicas Agropecuarias, los cuales son trabajados por los módulos de hortalizas y ornamentales. Las variables analizadas fueron: pH, densidad, textura, materia orgánica (M.O), nitrógeno, potasio, fosforo, calcio y magnesio. La evaluación toxicológica se realizó cualitativamente evaluando la presencia y/o ausencia de: toxafeno, diclorodifeniltricloroetano (DDT), diclorodifenildicloroetano (DDD), endrin en presencia de dieldrin y/o aldrin, heptacloro y heptacloro en presencia de otros insecticidad organoclorados. Las variables se analizaron utilizando el programa estadístico SAS “Statistical Analysis System y la comparación de medias se realizó por la prueba de Tukey. Para las variables: pH, M.O, N, K, P, Ca y Mg en el análisis estadístico se reportaron diferencia significativa entre tratamientos, con respecto a la densidad no se encontró diferencia significativa en ningún tratamiento. El T1 y T2 (Invernadero de hortalizas) para las variables de pH y materia orgánica se obtuvieron resultados de 7.12-7.5 y 5.1 % respectivamente los cuales se consideran ambientes propicios para uso agrícola, por otra parte se reportan en los tres invernaderos residuos tóxicos de DDT los cuales podrían deberse a la volatilidad y a su lenta degradación en el suelo