Achieving accurate FTIR measurements on high performance bandpass filters

The sources of ordinate error in FTIR spectrometers are reviewed with reference to measuring small out-of-band features in the spectra of bandpass filters. Procedures for identifying instrumental artefacts are described. It is shown that features well below 0.01%T can be measured reliably

Electron beam excitation of plasmonic modes in gold dimers

We report on the first realization of hyperspectral imaging for visualization and excitation of plasmon modes in dimers of 100 nm gold decahedra by a scanning electron beam

Advances in the modeling of the Iberian thermal lithosphere and perspectives on deep geothermal studies

Renewable energy sources are key to achieve the transition toward clean energy system. Among them, the geothermal energy has a production whose effectiveness requires sufficient understanding of the temperature distribution and fluid circulation at depth, as well as of the lithological and petrophysical properties of the crust. The focus of this paper is twofold: first, we summarize the main advances in the development of new methodologies and numerical codes to characterize the properties of the thermal lithosphere in terms of its, temperature, density and composition; second, based on the compilation of available thermal modelling results, we present the depth of the thermal Lithosphere-Asthenosphere Boundary (LAB) of the Iberian Peninsula and the temperature distribution at crustal depths of 5, 10, and 20 km, in addition to at Moho level. At 5 km depth, the temperature is above 110 °C with local anomalies (> 130 °C) located in the Iberian Massif and Cenozoic volcanic provinces. A similar pattern is observed at 10 and 20 km depth, where temperatures are above 190 °C and 350 °C, respectively. At 20 km depth, anomalies above > 500 °C, delineate the SE and NE Cenozoic volcanic provinces. At Moho depths, temperature ranges from 450 to 800 °C with hot regions mainly located along the Iberian Massif and the SE and NE volcanic provinces. The compiled results do not show any lithospheric anomaly that could give rise to high temperatures at shallow depths, but they do show an acceptable exploitation potential at intermediate depths. With regard to the direct use of district and greenhouse heating and for industrial processes, the potential is great throughout the Peninsula, the main challenges being the availability of groundwater and drilling costs

XPS characterization of Au (core)/SiO2 (shell) nanoparticles

Core-shell nanoparticles with ca. 15-nm gold core and 6-nm silica shell were prepared and characterized by XPS. The Au/Si atomic ratio determined by XPS is independent of the electron takeoff angle because of the concentric spherical shape of the nanoparticles. The formula given by Wertheim and DiCenzo (Phys. Rev. B 1988, 37, 844) for spherical nanoparticles and the modified one by Yang et al. (J. Appl. Phys. 2005, 97, 024303) for core-shell nanoparticles are used to correlate the XPS-derived composition with the geometry of the nanoparticles only after significantly modifying either the bulk density of the silica shell or the attenuation length of the photoelectrons. © 2005 American Chemical Society

Lectin-gated and glycan functionalized mesoporous silica nanocontainers for targeting cancer cells overexpressing Lewis X antigen

[EN] Gated mesoporous silica nanoparticles can deliver payload upon the application of a predefined stimulus, and therefore are promising drug delivery systems. Despite their important role, relatively low emphasis has been placed on the design of gating systems that actively target carbohydrate tumor cell membrane receptors. We describe herein a new Lewis X (Le(x)) antigen-targeted delivery system comprising mesoporous silica nanoparticles (MSNs) loaded with ATTO 430LS dye, functionalized with a Le(x) derivative (1) and capped with a fucose-specific carbohydrate-binding protein (Aleuria aurantia lectin (AAL)). This design takes advantage of the affinity of AAL for Le(x) overexpressed receptors in certain cancer cells. In the proximity of the cells, AAL is detached from MSNs to bind Le(x), and selectins in the cells bind Le(x) in the gated MSNs, thereby inducing cargo delivery. Gated MSNs are nontoxic to colon cancer DLD-1 cells, and ATTO 430LS dye delivered correlated with the amount of Le(x) antigen overexpressed at the DLD-1 cell surface. This is one of the few examples of MSNs using biologically relevant glycans for both capping (via interaction with AAL) and targeting (via interaction with overexpressed Le(x) at the cell membrane).The authors thank the Spanish Government (Projects MAT2015-64139-C4-1-R and MAT2013-46101-R (MINECO/ FEDER)), Fondo de Investigacion Sanitaria (PI15/00480) and Generalitat Valenciana (Project PROMETEOII/2014/047 and project GVA/2014/13) for support. R. B. is thankful to Svagata. Eu (Erasmus Mundus Action-II program) for his fellowship. The authors also thank the Electron Microscopy Service at the UPV for support.Bhat, R.; García, I.; Aznar, E.; Arnáiz, B.; Martínez-Bisbal, M.; Liz-Marzán, L.; Penadés, S.... (2018). Lectin-gated and glycan functionalized mesoporous silica nanocontainers for targeting cancer cells overexpressing Lewis X antigen. Nanoscale. 10(1):239-249. https://doi.org/10.1039/c7nr06415bS239249101Argyo, C., Weiss, V., Bräuchle, C., & Bein, T. (2013). Multifunctional Mesoporous Silica Nanoparticles as a Universal Platform for Drug Delivery. Chemistry of Materials, 26(1), 435-451. doi:10.1021/cm402592tAznar, E., Martínez-Máñez, R., & Sancenón, F. (2009). Controlled release using mesoporous materials containing gate-like scaffoldings. Expert Opinion on Drug Delivery, 6(6), 643-655. doi:10.1517/17425240902895980Aznar, E., Oroval, M., Pascual, L., Murguía, J. R., Martínez-Máñez, R., & Sancenón, F. (2016). Gated Materials for On-Command Release of Guest Molecules. Chemical Reviews, 116(2), 561-718. doi:10.1021/acs.chemrev.5b00456Wang, X., Tan, L.-L., Li, X., Song, N., Li, Z., Hu, J.-N., … Yang, Y.-W. (2016). Smart mesoporous silica nanoparticles gated by pillararene-modified gold nanoparticles for on-demand cargo release. Chemical Communications, 52(95), 13775-13778. doi:10.1039/c6cc08241fChen, X., Sun, H., Hu, J., Han, X., Liu, H., & Hu, Y. (2017). Transferrin gated mesoporous silica nanoparticles for redox-responsive and targeted drug delivery. Colloids and Surfaces B: Biointerfaces, 152, 77-84. doi:10.1016/j.colsurfb.2017.01.010Prasad, R., Aiyer, S., Chauhan, D. S., Srivastava, R., & Selvaraj, K. (2016). Bioresponsive carbon nano-gated multifunctional mesoporous silica for cancer theranostics. Nanoscale, 8(8), 4537-4546. doi:10.1039/c5nr06756aAgostini, A., Mondragón, L., Coll, C., Aznar, E., Marcos, M. D., Martínez-Máñez, R., … Amorós, P. (2012). Dual Enzyme-Triggered Controlled Release on Capped Nanometric Silica Mesoporous Supports. ChemistryOpen, 1(1), 17-20. doi:10.1002/open.201200003García-Fernández, A., García-Laínez, G., Ferrándiz, M. L., Aznar, E., Sancenón, F., Alcaraz, M. 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Chemical Communications, 48(45), 5647. doi:10.1039/c2cc31563gOroval, M., Climent, E., Coll, C., Eritja, R., Aviñó, A., Marcos, M. D., … Amorós, P. (2013). An aptamer-gated silica mesoporous material for thrombin detection. Chemical Communications, 49(48), 5480. doi:10.1039/c3cc42157kHe, D., He, X., Wang, K., Chen, M., Zhao, Y., & Zou, Z. (2013). Intracellular acid-triggered drug delivery system using mesoporous silica nanoparticles capped with T–Hg2+–T base pairs mediated duplex DNA. Journal of Materials Chemistry B, 1(11), 1552. doi:10.1039/c3tb00473bChen, L., Zhou, X., Nie, W., Zhang, Q., Wang, W., Zhang, Y., & He, C. (2016). Multifunctional Redox-Responsive Mesoporous Silica Nanoparticles for Efficient Targeting Drug Delivery and Magnetic Resonance Imaging. ACS Applied Materials & Interfaces, 8(49), 33829-33841. doi:10.1021/acsami.6b11802Croissant, J. G., Zhang, D., Alsaiari, S., Lu, J., Deng, L., Tamanoi, F., … Khashab, N. M. (2016). Protein-gold clusters-capped mesoporous silica nanoparticles for high drug loading, autonomous gemcitabine/doxorubicin co-delivery, and in-vivo tumor imaging. Journal of Controlled Release, 229, 183-191. doi:10.1016/j.jconrel.2016.03.030Oroval, M., Díez, P., Aznar, E., Coll, C., Marcos, M. D., Sancenón, F., … Martínez-Máñez, R. (2016). Self-Regulated Glucose-Sensitive Neoglycoenzyme-Capped Mesoporous Silica Nanoparticles for Insulin Delivery. Chemistry - A European Journal, 23(6), 1353-1360. doi:10.1002/chem.201604104Chen, C., Geng, J., Pu, F., Yang, X., Ren, J., & Qu, X. (2010). Polyvalent Nucleic Acid/Mesoporous Silica Nanoparticle Conjugates: Dual Stimuli-Responsive Vehicles for Intracellular Drug Delivery. Angewandte Chemie International Edition, 50(4), 882-886. doi:10.1002/anie.201005471Yang, X., Liu, X., Liu, Z., Pu, F., Ren, J., & Qu, X. (2012). Near-Infrared Light-Triggered, Targeted Drug Delivery to Cancer Cells by Aptamer Gated Nanovehicles. Advanced Materials, 24(21), 2890-2895. doi:10.1002/adma.201104797Deng, Z., Zhen, Z., Hu, X., Wu, S., Xu, Z., & Chu, P. K. (2011). Hollow chitosan–silica nanospheres as pH-sensitive targeted delivery carriers in breast cancer therapy. Biomaterials, 32(21), 4976-4986. doi:10.1016/j.biomaterials.2011.03.050Palanikumar, L., Choi, E. S., Cheon, J. Y., Joo, S. H., & Ryu, J.-H. (2014). Noncovalent Polymer-Gatekeeper in Mesoporous Silica Nanoparticles as a Targeted Drug Delivery Platform. Advanced Functional Materials, 25(6), 957-965. doi:10.1002/adfm.201402755Li, L.-L., Xie, M., Wang, J., Li, X., Wang, C., Yuan, Q., … Tan, W. (2013). A vitamin-responsive mesoporous nanocarrier with DNA aptamer-mediated cell targeting. Chemical Communications, 49(52), 5823. doi:10.1039/c3cc41072bHäuselmann, I., & Borsig, L. (2014). Altered Tumor-Cell Glycosylation Promotes Metastasis. Frontiers in Oncology, 4. doi:10.3389/fonc.2014.00028Haltiwanger, R. S., & Lowe, J. B. (2004). Role of Glycosylation in Development. Annual Review of Biochemistry, 73(1), 491-537. doi:10.1146/annurev.biochem.73.011303.074043A. Varki , R.Kannagi and B. P.Toole , Glycosylation Changes in Cancer , Cold Spring Harbor Laboratory Press , 2009A. Varki and J. B.Lowe , Biological Roles of Glycans , Cold Spring Harbor Laboratory Press , 2009Gary-Bobo, M., Hocine, O., Brevet, D., Maynadier, M., Raehm, L., Richeter, S., … Durand, J.-O. (2012). Cancer therapy improvement with mesoporous silica nanoparticles combining targeting, drug delivery and PDT. International Journal of Pharmaceutics, 423(2), 509-515. doi:10.1016/j.ijpharm.2011.11.045Brevet, D., Gary-Bobo, M., Raehm, L., Richeter, S., Hocine, O., Amro, K., … Durand, J.-O. (2009). Mannose-targeted mesoporous silica nanoparticles for photodynamic therapy. Chemical Communications, (12), 1475. doi:10.1039/b900427kHocine, O., Gary-Bobo, M., Brevet, D., Maynadier, M., Fontanel, S., Raehm, L., … Frochot, C. (2010). Silicalites and Mesoporous Silica Nanoparticles for photodynamic therapy. International Journal of Pharmaceutics, 402(1-2), 221-230. doi:10.1016/j.ijpharm.2010.10.004Park, I. Y., Kim, I. Y., Yoo, M. K., Choi, Y. J., Cho, M.-H., & Cho, C. S. (2008). Mannosylated polyethylenimine coupled mesoporous silica nanoparticles for receptor-mediated gene delivery. International Journal of Pharmaceutics, 359(1-2), 280-287. doi:10.1016/j.ijpharm.2008.04.010Luo, Z., Cai, K., Hu, Y., Zhao, L., Liu, P., Duan, L., & Yang, W. (2010). Mesoporous Silica Nanoparticles End-Capped with Collagen: Redox-Responsive Nanoreservoirs for Targeted Drug Delivery. Angewandte Chemie International Edition, 50(3), 640-643. doi:10.1002/anie.201005061PENG, J., WANG, K., TAN, W., HE, X., HE, C., WU, P., & LIU, F. (2007). Identification of live liver cancer cells in a mixed cell system using galactose-conjugated fluorescent nanoparticles. Talanta, 71(2), 833-840. doi:10.1016/j.talanta.2006.05.064Yu, M., Jambhrunkar, S., Thorn, P., Chen, J., Gu, W., & Yu, C. (2013). Hyaluronic acid modified mesoporous silica nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells. Nanoscale, 5(1), 178-183. doi:10.1039/c2nr32145aHe, Q., Ma, M., Wei, C., & Shi, J. (2012). Mesoporous carbon@silicon-silica nanotheranostics for synchronous delivery of insoluble drugs and luminescence imaging. Biomaterials, 33(17), 4392-4402. doi:10.1016/j.biomaterials.2012.02.056Wu, S., Huang, X., & Du, X. (2013). Glucose- and pH-Responsive Controlled Release of Cargo from Protein-Gated Carbohydrate-Functionalized Mesoporous Silica Nanocontainers. Angewandte Chemie International Edition, 52(21), 5580-5584. doi:10.1002/anie.201300958Li, J., Qu, X., Payne, G. F., Zhang, C., Zhang, Y., Li, J., … Liu, C. (2015). Biospecific Self-Assembly of a Nanoparticle Coating for Targeted and Stimuli-Responsive Drug Delivery. Advanced Functional Materials, 25(9), 1404-1417. doi:10.1002/adfm.201403636Burchell, J., Poulsom, R., Hanby, A., Whitehouse, C., Cooper, L., Clausen, H., … Taylor-Papadimitriou, J. (1999). An  2,3 sialyltransferase (ST3Gal I) is elevated in primary breast carcinomas. Glycobiology, 9(12), 1307-1311. doi:10.1093/glycob/9.12.1307Pinho, S. S., Reis, C. A., Paredes, J., Magalhaes, A. M., Ferreira, A. C., Figueiredo, J., … Seruca, R. (2009). The role of N-acetylglucosaminyltransferase III and V in the post-transcriptional modifications of E-cadherin. Human Molecular Genetics, 18(14), 2599-2608. doi:10.1093/hmg/ddp194Takahashi, M., Kuroki, Y., Ohtsubo, K., & Taniguchi, N. (2009). Core fucose and bisecting GlcNAc, the direct modifiers of the N-glycan core: their functions and target proteins. Carbohydrate Research, 344(12), 1387-1390. doi:10.1016/j.carres.2009.04.031Li, M., Song, L., & Qin, X. (2010). Glycan changes: cancer metastasis and anti-cancer vaccines. Journal of Biosciences, 35(4), 665-673. doi:10.1007/s12038-010-0073-8Nagao, K., Itoh, Y., Fujita, K., & Fujime, M. (2007). Evaluation of urinary CA19-9 levels in bladder cancer patients classified according to the combinations of Lewis and Secretor blood group genotypes. International Journal of Urology, 14(9), 795-799. doi:10.1111/j.1442-2042.2007.01840.xGao, W., Liang, J., & Liang, Y. (2016). Clinicopathological and prognostic significance of sialyl Lewis X overexpression in patients with cancer: a meta-analysis. OncoTargets and Therapy, 3113. doi:10.2147/ott.s102389Sozzani, P., Arisio, R., Porpiglia, M., & Benedetto, C. (2008). Is Sialyl Lewis x Antigen Expression a Prognostic Factor in Patients With Breast Cancer? International Journal of Surgical Pathology, 16(4), 365-374. doi:10.1177/1066896908324668Yusa, A., Miyazaki, K., Kimura, N., Izawa, M., & Kannagi, R. (2010). Epigenetic Silencing of the Sulfate Transporter Gene DTDST Induces Sialyl Lewisx Expression and Accelerates Proliferation of Colon Cancer Cells. Cancer Research, 70(10), 4064-4073. doi:10.1158/0008-5472.can-09-2383Golijanin, D., Sherman, Y., Shapiro, A., & Pode, D. (1995). Detection of bladder tumors by immunostaininc of the lewis x antigen in cells from voided urine. Urology, 46(2), 173-177. doi:10.1016/s0090-4295(99)80189-7Hittelet, A., Camby, I., Nagy, N., Legendre, H., Bronckart, Y., Decaestecker, C., … Yeaton, P. (2003). Binding Sites for Lewis Antigens Are Expressed by Human Colon Cancer Cells and Negatively Affect Their Migration. Laboratory Investigation, 83(6), 777-787. doi:10.1097/01.lab.0000073129.62433.39De la Torre, C., Casanova, I., Acosta, G., Coll, C., Moreno, M. J., Albericio, F., … Martínez-Máñez, R. (2014). 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Joint interpretation of magnetotelluric, seismic, and well-log data in Hontomín (Spain)

Hontomín (N of Spain) hosts the first Spanish CO2 storage pilot plant. The subsurface characterization of the site included the acquisition of a 3-D seismic reflection and a circumscribed 3-D magnetotelluric (MT) survey. This paper addresses the combination of the seismic and MT results, together with the available well-log data, in order to achieve a better characterization of the Hontomín subsurface. We compare the structural model obtained from the interpretation of the seismic data with the geoelectrical model resulting from the MT data. The models correlate well in the surroundings of the CO2 injection area with the major structural differences observed related to the presence of faults. The combination of the two methods allowed a more detailed characterization of the faults, defining their geometry, and fluid flow characteristics, which are key for the risk assessment of the storage site. Moreover, we use the well-log data of the existing wells to derive resistivity-velocity relationships for the subsurface and compute a 3-D velocity model of the site using the 3-D resistivity model as a reference. The derived velocity model is compared to both the predicted and logged velocity in the injection and monitoring wells, for an overall assessment of the computed resistivity-velocity relationships. The major differences observed are explained by the different resolution of the compared geophysical methods. Finally, the derived velocity model for the near surface is compared with the velocity model used for the static corrections in the seismic data. The results allowed extracting information about the characteristics of the shallow unconsolidated sediments, suggesting possible clay and water content variations. The good correlation of the velocity models derived from the resistivity-velocity relationships and the well-log data demonstrate the potential of the combination of the two methods for characterizing the subsurface, in terms of its physical properties (velocity, resistivity) and structural/reservoir characteristics. This work explores the compatibility of the seismic and magnetotelluric methods across scales highlighting the importance of joint interpretation in near surface and reservoir characterization

Evidence of random magnetic anisotropy in ferrihydrite nanoparticles based on analysis of statistical distributions

We show that the magnetic anisotropy energy of antiferromagnetic ferrihydrite depends on the square root of the nanoparticles volume, using a method based on the analysis of statistical distributions. The size distribution was obtained by transmission electron microscopy, and the anisotropy energy distributions were obtained from ac magnetic susceptibility and magnetic relaxation. The square root dependence corresponds to random local anisotropy, whose average is given by its variance, and can be understood in terms of the recently proposed single phase homogeneous structure of ferrihydrite.Comment: 6 pages, 2 figure

Robust plasmon waveguides in strongly-interacting nanowire arrays

Arrays of parallel metallic nanowires are shown to provide a tunable, robust, and versatile platform for plasmon interconnects, including high-curvature turns with minimum signal loss. The proposed guiding mechanism relies on gap plasmons existing in the region between adjacent nanowires of dimers and multi-wire arrays. We focus on square and circular silver nanowires in silica, for which excellent agreement between both boundary element method and multiple multipolar expansion calculations is obtained. Our work provides the tools for designing plasmon-based interconnects and achieving high degree of integration with minimum cross talk between adjacent plasmon guides.Comment: 4 pages, 5 figure

Optical response of Ag-Au bimetallic nanoparticles to electron storage in aqueous medium

Composition and structure dependence of the shift in the position of the surface plasmon resonance band upon introduction of NaBH 4 to aqueous solutions of gold and silver nanoparticles are presented. Silver and gold nanoalloys in different compositions were prepared by co-reduction of the corresponding salt mixtures using sodium citrate as the reducing agent. After addition of NaBH 4 to the resultant nanoalloys, the maximum of their surface plasmon resonance band, ranging between that of pure silver (ca. 400 nm) and of pure gold (ca. 530 nm), is blue-shifted as a result of electron storage on the particles. The extent of this blue shift increases non-linearly with the mole fraction of silver in the nanoparticle, parallel to the trends reported previously for both the frequency and the extinction coefficient of the plasmon band shifts. Gold(core)@silver(shell) nanoparticles were prepared by sequential reduction of gold and silver, where addition of NaBH 4 results in relatively large spectral shift in the plasmon resonance band when compared with the nanoalloys having a similar overall composition. The origin of the large plasmon band shift in the core-shell is related with a higher silver surface concentration on these particles. Hence, the chemical nature of the nanoparticle emerges as the dominating factor contributing to the extent of the spectral shift as a result of electron storage in bimetallic systems. Copyright © 2008 American Scientific Publishers All rights reserved

Seismic characterization of the Alhama de Murcia Fault

La falla de Alhama de Murcia (AMF) es una de las fallas más activas de la Península Ibérica y fue la causante del terremoto de Lorca de 2011 que significó numerosos daños materiales e incluso víctimas mortales. Esta falla oblicua en dirección NE-SO, que se extiende por más de 100 km, ha sido estudiada en superficie pero poco se sabe de su estructura en profundidad. Esto es especialmente importante para poder interpretar de forma correcta los numerosos datos paleosísmicos que se están obteniendo, ya que conocer la relación estructural en profundidad de las distintas ramas que forman la AMF es esencial. Por este motivo, y dentro del marco del proyecto InterGEO, se ha realizado una campaña de adquisición de datos sísmicos 2D a lo largo de la AMF, centrándose en los segmentos más interesantes en la zona de Lorca-Totana. Aquí se presentan los los resultados preliminares del procesado de algunos de los perfiles adquiridos en esta campaña que muestran la primera imagen estructural de la falla en profundidad y que permitirá entender el comportamiento de dicha falla, así como determinar su relevancia desde el punto de vista del riesgo sísmico.The Alhama de Murcia fault (AMF) is one of the most active faults of the Iberian Peninsula and the source of the Lorca 2011 earthquake that caused significant damage including several casualties. This NE-SW oblique fault, extended more than 100 km, has been extensively mapped to characterize its surface structure but almost no information is available of the structure and geometry at depth. This is specially significant in order to correctly interpret the obtained paleoseismic data considering that the knowledge of the structural relationship in depth between different branches of the fault is necessary. Accordingly, and within the InterGEO project, a 2D seismic reflection acquisition experiment was carried out along the AMF, focusing in the more interesting segments in the Lorca-Totana area. In this work we present the very first results of the acquired seismic reflection profiles that show the first structural image in depth of this fault which allow us to understand the seismic behaviour of the fault, and determine its relevance in seismic hazard.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Economía y Competitividad (MINECO)Generalitat de Catalunyapu