Homogeneous and heterogeneous catalytic reduction of amides and related compounds using molecular hydrogen

Catalytic hydrogenation of amides is of great interest for chemists working in organic synthesis, as the resulting amines are widely featured in natural products, drugs, agrochemicals, dyes, etc. Compared to traditional reduction of amides using (over)stoichiometric reductants, the direct hydrogenation of amides using molecular hydrogen represents a greener approach. Furthermore, amide hydrogenation is a highly versatile transformation, since not only higher amines (obtained by C–O cleavage), but also lower amines and alcohols, or amino alcohols (obtained by C–N cleavage) can be selectively accessed by fine tuning of reaction conditions. This review describes the most recent advances in the area of amide hydrogenation using H2 exclusively and molecularly defined homogeneous as well as nano-structured heterogeneous catalysts, with a special focus on catalyst development and synthetic applications

Effects of polymethylmethacrylate-transfer residues on the growth of organic semiconductor molecules on chemical vapor deposited graphene

Scalably grown and transferred graphene is a highly promising material for organic electronic applications, but controlled interfacing of graphene thereby remains a key challenge. Here, we study the growth characteristics of the important organic semiconductor molecule para-hexaphenyl (6P) on chemical vapor deposited graphene that has been transferred with polymethylmethacrylate (PMMA) onto oxidized Si wafer supports. A particular focus is on the influence of PMMA residual contamination, which we systematically reduce by H2 annealing prior to 6P deposition. We find that 6P grows in a flat-lying needle-type morphology, surprisingly independent of the level of PMMA residue and of graphene defects. Wrinkles in the graphene typically act as preferential nucleation centers. Residual PMMA does however limit the length of the resulting 6P needles by restricting molecular diffusion/attachment. We discuss the implications for organic device fabrication, with particular regard to contamination and defect tolerance.B.C.B acknowledges a College Research Fellowship from Hughes Hall, Cambridge. P.R.K. acknowledges the Lindemann Trust Fellowship. A.M. and G.R. acknowledge support by the Serbian MPNTR through Projects OI 171005 and III 45018. R.S.W. acknowledges a research fellowship from St. John’s College, Cambridge. S.H. acknowledges funding from EPSRC (GRAPHTED, Grant No. EP/K016636/1). We want to thank Dr. Sarah M. Skoff (Vienna University of Technology, Austria) for fruitful discussions.This is the author accepted manuscript. The final published version is available via AIP at http://scitation.aip.org/content/aip/journal/apl/106/10/10.1063/1.4913948

A Semiconducting Bi2O2(C4O4) Coordination Polymer Showing a Photoelectric Response

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.9b03290.[EN] Inorganic semiconductors are extensively considered to be among the most promising materials to convert solar light into electricity or chemical energy owing to their efficiency in the separation of photoinduced electron/hole. Bismuth oxides, and, in particular, those built up of [Bi2O2](2+) layers, show an efficient charge separation and, thus, high photocatalytic activities. To explore a possible synergetic effect of bismuth metallic nodes combined with the electron-rich linker squarate, Bi2O2(C4O4) or IEF-3 (an IMDEA Energy framework) was hydrothermally prepared and adequately characterized. As determined from the X-ray structure, [Bi2O2](2+) layers are interconnected by squarate ligands, having a pronounced effect of the 6s(2) lone pair on the bismuth local environment. IEF-3 shows high thermal and chemical robustness at industrially relevant model aggressive media. A large panel of physicochemical methods were applied to recognize IEF-3 as an UV-absorbing n-type semiconductor, showing a photocurrent response comparable to that of alpha-Bi2O3, offering further possibilities for tuning its electrochemical properties by modifying the ligand. In this way, the well-known compositional and structural versatility of coordination polymers may be applied in the future to fine-tune metal-organic semiconductor systems.The authors acknowledge Ra-Phuel (Grant ENE2016-79608-C2-1-R), Ramon y Cajal Grant RYC-2014-15039 (Ministerio de Ciencia, Investigacion y Universidades), and Fundacion Ramon Areces (H + MOFs) for financial support. S.N. is thankful for financial support by the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016), Ministerio de Ciencia, Innovacion y Universidades project (Project RTI2018-099482-A-I00), and Generalitat Valenciana grupos de investigacion consolidables 2019 (ref: AICO/2019/214) project. H.G. is thankful for financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa SEV2016 and RTI2018-890237-CO2-1), and Generalitat Valenciana (Prometeo 2017/083) is also gratefully acknowledged.Babaryk, AA.; Contreras Almengor, OR.; Cabrero-Antonino, M.; Navalón Oltra, S.; García Gómez, H.; Horcajada, P. (2020). A Semiconducting Bi2O2(C4O4) Coordination Polymer Showing a Photoelectric Response. Inorganic Chemistry. 59(6):3406-3416. https://doi.org/10.1021/acs.inorgchem.9b03290S34063416596Lund, H. (2007). Renewable energy strategies for sustainable development. Energy, 32(6), 912-919. doi:10.1016/j.energy.2006.10.017Omer, A. M. (2008). Energy, environment and sustainable development. Renewable and Sustainable Energy Reviews, 12(9), 2265-2300. doi:10.1016/j.rser.2007.05.001Crabtree, G. W., & Lewis, N. S. (2007). Solar energy conversion. Physics Today, 60(3), 37-42. doi:10.1063/1.2718755Gust, D., Moore, T. A., & Moore, A. L. (2009). Solar Fuels via Artificial Photosynthesis. Accounts of Chemical Research, 42(12), 1890-1898. doi:10.1021/ar900209bArakawa, H., & Sayama, K. (2000). Oxide semiconductor materials for solar light energy utilization. Research on Chemical Intermediates, 26(2), 145-152. doi:10.1163/156856700x00183Sang, Y., Liu, H., & Umar, A. (2014). Photocatalysis from UV/Vis to Near-Infrared Light: Towards Full Solar-Light Spectrum Activity. ChemCatChem, 7(4), 559-573. doi:10.1002/cctc.201402812Wang, Q., & Domen, K. (2019). Particulate Photocatalysts for Light-Driven Water Splitting: Mechanisms, Challenges, and Design Strategies. Chemical Reviews, 120(2), 919-985. doi:10.1021/acs.chemrev.9b00201Liu, Z., & Yan, F. (2012). The Application of Bismuth-Based Oxides in Organic-Inorganic Hybrid Photovoltaic Devices. Journal of the American Ceramic Society, 95(6), 1944-1948. doi:10.1111/j.1551-2916.2012.05088.xRaza, W., Haque, M. M., Muneer, M., Harada, T., & Matsumura, M. (2015). Synthesis, characterization and photocatalytic performance of visible light induced bismuth oxide nanoparticle. Journal of Alloys and Compounds, 648, 641-650. doi:10.1016/j.jallcom.2015.06.245Gomez, C. L., Depablos-Rivera, O., Silva-Bermudez, P., Muhl, S., Zeinert, A., Lejeune, M., … Rodil, S. E. (2015). Opto-electronic properties of bismuth oxide films presenting different crystallographic phases. Thin Solid Films, 578, 103-112. doi:10.1016/j.tsf.2015.02.020MEDERNACH, J. W., & SNYDER, R. L. (1978). Powder Diffraction Patterns and Structures of the Bismuth Oxides. Journal of the American Ceramic Society, 61(11-12), 494-497. doi:10.1111/j.1151-2916.1978.tb16125.xLeontie, L., Caraman, M., Alexe, M., & Harnagea, C. (2002). Structural and optical characteristics of bismuth oxide thin films. Surface Science, 507-510, 480-485. doi:10.1016/s0039-6028(02)01289-xXiao, X., Liu, C., Hu, R., Zuo, X., Nan, J., Li, L., & Wang, L. (2012). Oxygen-rich bismuth oxyhalides: generalized one-pot synthesis, band structures and visible-light photocatalytic properties. Journal of Materials Chemistry, 22(43), 22840. doi:10.1039/c2jm33556eWeidong, H., Wei, Q., Xiaohong, W., Xianbo, D., Long, C., & Zhaohua, J. (2007). The photocatalytic properties of bismuth oxide films prepared through the sol–gel method. Thin Solid Films, 515(13), 5362-5365. doi:10.1016/j.tsf.2007.01.031Duan, F., Zheng, Y., Liu, L., Chen, M., & Xie, Y. (2010). Synthesis and photocatalytic behaviour of 3D flowerlike bismuth oxide formate architectures. Materials Letters, 64(14), 1566-1569. doi:10.1016/j.matlet.2010.04.046Lee, G.-J., Zheng, Y.-C., & Wu, J. J. (2018). Fabrication of hierarchical bismuth oxyhalides (BiOX, X = Cl, Br, I) materials and application of photocatalytic hydrogen production from water splitting. Catalysis Today, 307, 197-204. doi:10.1016/j.cattod.2017.04.044Huang, H., He, Y., Lin, Z., Kang, L., & Zhang, Y. (2013). Two Novel Bi-Based Borate Photocatalysts: Crystal Structure, Electronic Structure, Photoelectrochemical Properties, and Photocatalytic Activity under Simulated Solar Light Irradiation. The Journal of Physical Chemistry C, 117(44), 22986-22994. doi:10.1021/jp4084184Liu, Y., Wang, Z., Huang, B., Yang, K., Zhang, X., Qin, X., & Dai, Y. (2010). Preparation, electronic structure, and photocatalytic properties of Bi2O2CO3 nanosheet. Applied Surface Science, 257(1), 172-175. doi:10.1016/j.apsusc.2010.06.058Huang, H., He, Y., Li, X., Li, M., Zeng, C., Dong, F., … Zhang, Y. (2015). Bi2O2(OH)(NO3) as a desirable [Bi2O2]2+layered photocatalyst: strong intrinsic polarity, rational band structure and {001} active facets co-beneficial for robust photooxidation capability. Journal of Materials Chemistry A, 3(48), 24547-24556. doi:10.1039/c5ta07655bRuleova, P., Drasar, C., Lostak, P., Li, C.-P., Ballikaya, S., & Uher, C. (2010). Thermoelectric properties of Bi2O2Se. Materials Chemistry and Physics, 119(1-2), 299-302. doi:10.1016/j.matchemphys.2009.08.067Luu, S. D. N., & Vaqueiro, P. (2015). Synthesis, characterisation and thermoelectric properties of the oxytelluride Bi2O2Te. Journal of Solid State Chemistry, 226, 219-223. doi:10.1016/j.jssc.2015.02.026Yu, X., Marks, T. J., & Facchetti, A. (2016). Metal oxides for optoelectronic applications. Nature Materials, 15(4), 383-396. doi:10.1038/nmat4599Alvaro, M., Carbonell, E., Ferrer, B., Llabrés i Xamena, F. X., & Garcia, H. (2007). Semiconductor Behavior of a Metal-Organic Framework (MOF). Chemistry - A European Journal, 13(18), 5106-5112. doi:10.1002/chem.200601003Usman, M., Mendiratta, S., & Lu, K.-L. (2016). Semiconductor Metal-Organic Frameworks: Future Low-Bandgap Materials. Advanced Materials, 29(6), 1605071. doi:10.1002/adma.201605071Tachikawa, T., Choi, J. R., Fujitsuka, M., & Majima, T. (2008). Photoinduced Charge-Transfer Processes on MOF-5 Nanoparticles: Elucidating Differences between Metal-Organic Frameworks and Semiconductor Metal Oxides. The Journal of Physical Chemistry C, 112(36), 14090-14101. doi:10.1021/jp803620vFeyand, M., Mugnaioli, E., Vermoortele, F., Bueken, B., Dieterich, J. M., Reimer, T., … Stock, N. (2012). Automated Diffraction Tomography for the Structure Elucidation of Twinned, Sub-micrometer Crystals of a Highly Porous, Catalytically Active Bismuth Metal-Organic Framework. Angewandte Chemie International Edition, 51(41), 10373-10376. doi:10.1002/anie.201204963Wang, G., Sun, Q., Liu, Y., Huang, B., Dai, Y., Zhang, X., & Qin, X. (2014). A Bismuth-Based Metal-Organic Framework as an Efficient Visible-Light-Driven Photocatalyst. Chemistry - A European Journal, 21(6), 2364-2367. doi:10.1002/chem.201405047Wang, G., Liu, Y., Huang, B., Qin, X., Zhang, X., & Dai, Y. (2015). A novel metal–organic framework based on bismuth and trimesic acid: synthesis, structure and properties. Dalton Transactions, 44(37), 16238-16241. doi:10.1039/c5dt03111gWang, Y., Takki, S., Cheung, O., Xu, H., Wan, W., Öhrström, L., & Inge, A. K. (2017). Elucidation of the elusive structure and formula of the active pharmaceutical ingredient bismuth subgallate by continuous rotation electron diffraction. Chemical Communications, 53(52), 7018-7021. doi:10.1039/c7cc03180gKöppen, M., Dhakshinamoorthy, A., Inge, A. K., Cheung, O., Ångström, J., Mayer, P., & Stock, N. (2018). Synthesis, Transformation, Catalysis, and Gas Sorption Investigations on the Bismuth Metal-Organic Framework CAU-17. European Journal of Inorganic Chemistry, 2018(30), 3496-3503. doi:10.1002/ejic.201800321Gándara, F., Gómez-Lor, B., Iglesias, M., Snejko, N., Gutiérrez-Puebla, E., & Monge, A. (2009). A new scandium metal organic framework built up from octadecasil zeolitic cages as heterogeneous catalyst. Chemical Communications, (17), 2393. doi:10.1039/b900841aGoswami, S., Adhikary, A., Jena, H. S., Biswas, S., & Konar, S. (2013). A 3D Iron(II)-Based MOF with Squashed Cuboctahedral Nanoscopic Cages Showing Spin-Canted Long-Range Antiferromagnetic Ordering. Inorganic Chemistry, 52(20), 12064-12069. doi:10.1021/ic401886fUsov, P. M., Keene, T. D., & D’Alessandro, D. M. (2013). A Comparative Study of the Structural, Optical, and Electrochemical Properties of Squarate-Based Coordination Frameworks. Australian Journal of Chemistry, 66(4), 429. doi:10.1071/ch12474Liu, Z., Lin, K., Ren, Y., Kato, K., Cao, Y., Deng, J., … Xing, X. (2019). Inorganic–organic hybridization induced uniaxial zero thermal expansion in MC4O4 (M = Ba, Pb). Chemical Communications, 55(28), 4107-4110. doi:10.1039/c9cc00226jAllen, L. C. (1989). Electronegativity is the average one-electron energy of the valence-shell electrons in ground-state free atoms. Journal of the American Chemical Society, 111(25), 9003-9014. doi:10.1021/ja00207a003Goswami, S., Jena, H. S., & Konar, S. (2014). Study of Heterogeneous Catalysis by Iron-Squarate based 3D Metal Organic Framework for the Transformation of Tetrazines to Oxadiazole derivatives. Inorganic Chemistry, 53(14), 7071-7073. doi:10.1021/ic5003258Lin, R.-B., Li, L., Zhou, H.-L., Wu, H., He, C., Li, S., … Chen, B. (2018). Molecular sieving of ethylene from ethane using a rigid metal–organic framework. Nature Materials, 17(12), 1128-1133. doi:10.1038/s41563-018-0206-2Li, L., Guo, L., Zhang, Z., Yang, Q., Yang, Y., Bao, Z., … Li, J. (2019). A Robust Squarate-Based Metal–Organic Framework Demonstrates Record-High Affinity and Selectivity for Xenon over Krypton. Journal of the American Chemical Society, 141(23), 9358-9364. doi:10.1021/jacs.9b03422Wang, Ke, Feng, Ho, Chang, Chuang, & Lee. (2019). Synthesis, Structural Characterization and Ligand-Enhanced Photo-Induced Color-Changing Behavior of Two Hydrogen-Bonded Ho(III)-Squarate Supramolecular Compounds. Polymers, 11(8), 1369. doi:10.3390/polym11081369Boultif, A., & Louër, D. (2004). Powder pattern indexing with the dichotomy method. Journal of Applied Crystallography, 37(5), 724-731. doi:10.1107/s0021889804014876De Wolff, P. M. (1968). A simplified criterion for the reliability of a powder pattern indexing. Journal of Applied Crystallography, 1(2), 108-113. doi:10.1107/s002188986800508xAltomare, A., Cuocci, C., Giacovazzo, C., Moliterni, A., Rizzi, R., Corriero, N., & Falcicchio, A. (2013). EXPO2013: a kit of tools for phasing crystal structures from powder data. Journal of Applied Crystallography, 46(4), 1231-1235. doi:10.1107/s0021889813013113Spek, A. L. (2009). Structure validation in chemical crystallography. Acta Crystallographica Section D Biological Crystallography, 65(2), 148-155. doi:10.1107/s090744490804362xRietveld, H. M. (1969). A profile refinement method for nuclear and magnetic structures. Journal of Applied Crystallography, 2(2), 65-71. doi:10.1107/s0021889869006558Gonze, X., Amadon, B., Anglade, P.-M., Beuken, J.-M., Bottin, F., Boulanger, P., … Zwanziger, J. W. (2009). ABINIT: First-principles approach to material and nanosystem properties. Computer Physics Communications, 180(12), 2582-2615. doi:10.1016/j.cpc.2009.07.007Perdew, J. P., Ruzsinszky, A., Csonka, G. I., Vydrov, O. A., Scuseria, G. E., Constantin, L. A., … Burke, K. (2008). Restoring the Density-Gradient Expansion for Exchange in Solids and Surfaces. Physical Review Letters, 100(13). doi:10.1103/physrevlett.100.136406Hamann, D. R. (2013). Optimized norm-conserving Vanderbilt pseudopotentials. Physical Review B, 88(8). doi:10.1103/physrevb.88.085117Hinuma, Y., Pizzi, G., Kumagai, Y., Oba, F., & Tanaka, I. (2017). Band structure diagram paths based on crystallography. Computational Materials Science, 128, 140-184. doi:10.1016/j.commatsci.2016.10.015Becke, A. D., & Johnson, E. R. (2006). A simple effective potential for exchange. The Journal of Chemical Physics, 124(22), 221101. doi:10.1063/1.2213970Tran, F., & Blaha, P. (2009). Accurate Band Gaps of Semiconductors and Insulators with a Semilocal Exchange-Correlation Potential. Physical Review Letters, 102(22). doi:10.1103/physrevlett.102.226401Christensen, A. N., Jensen, T. R., Scarlett, N. V. Y., Madsen, I. C., Hanson, J. C., & Altomare, A. (2003). In-situ X-ray powder diffraction studies of hydrothermal and thermal decomposition reactions of basic bismuth(iii) nitrates in the temperature range 20–650 °C. Dalton Trans., (16), 3278-3282. doi:10.1039/b303926aSuzuki, H., Kunioku, H., Higashi, M., Tomita, O., Kato, D., Kageyama, H., & Abe, R. (2018). Lead Bismuth Oxyhalides PbBiO2X (X = Cl, Br) as Visible-Light-Responsive Photocatalysts for Water Oxidation: Role of Lone-Pair Electrons in Valence Band Engineering. Chemistry of Materials, 30(17), 5862-5869. doi:10.1021/acs.chemmater.8b01385Wu, X., Li, M., Li, J., Zhang, G., & Yin, S. (2017). A sillenite-type Bi12MnO20 photocatalyst: UV, visible and infrared lights responsive photocatalytic properties induced by the hybridization of Mn 3d and O 2p orbitals. Applied Catalysis B: Environmental, 219, 132-141. doi:10.1016/j.apcatb.2017.07.025Millet, P., Sabadié, L., Galy, J., & Trombe, J. . (2003). Hydrothermal synthesis and structure of the first tin(II) squarate Sn2O(C4O4)(H2O)—comparison with Sn2[Sn2O2F4]. Journal of Solid State Chemistry, 173(1), 49-53. doi:10.1016/s0022-4596(03)00078-1Bataille, T., Bouhali, A., Kouvatas, C., Trifa, C., Audebrand, N., & Boudaren, C. (2019). Hydrates and polymorphs of lead squarate Pb(C4O4): Structural transformations studied by in situ X-ray powder diffraction and solid state NMR. Polyhedron, 164, 123-131. doi:10.1016/j.poly.2019.02.047Kroumova, E., Aroyo, M. I., Perez-Mato, J. M., Kirov, A., Capillas, C., Ivantchev, S., & Wondratschek, H. (2003). Bilbao Crystallographic Server : Useful Databases and Tools for Phase-Transition Studies. Phase Transitions, 76(1-2), 155-170. doi:10.1080/0141159031000076110Junqueira, G. M. A., Rocha, W. R., De Almeida, W. B., & Dos Santos, H. F. (2002). Theoretical analysis of the oxocarbons: The solvent and counter-ion effects on the structure and spectroscopic properties of the squarate ion. Physical Chemistry Chemical Physics, 5(3), 437-445. doi:10.1039/b209740kCao, J., Xu, B., Lin, H., Luo, B., & Chen, S. (2012). Novel heterostructured Bi2S3/BiOI photocatalyst: facile preparation, characterization and visible light photocatalytic performance. Dalton Transactions, 41(37), 11482. doi:10.1039/c2dt30883eKeller, E., & Krämer, V. (2005). A Strong Deviation from Vegard’s Rule: X-Ray Powder Investigations of the Three Quasi-Binary Phase Systems BiOX–BiOY (X, Y = Cl, Br, I). Zeitschrift für Naturforschung B, 60(12), 1255-1263. doi:10.1515/znb-2005-1207Gao, X., Zhao, H., Zhao, X., Li, Z., Gao, Z., Wang, Y., & Huang, H. (2018). Aqueous phase sensing of bismuth ion using fluorescent metal-organic framework. Sensors and Actuators B: Chemical, 266, 323-328. doi:10.1016/j.snb.2018.03.139Deibert, B. J., Velasco, E., Liu, W., Teat, S. J., Lustig, W. P., & Li, J. (2016). High-Performance Blue-Excitable Yellow Phosphor Obtained from an Activated Solvochromic Bismuth-Fluorophore Metal–Organic Framework. Crystal Growth & Design, 16(8), 4178-4182. doi:10.1021/acs.cgd.6b00622De Mello DonegÁ, C., Ribeiro, S. J. L., Gon çalves, R. R., & Blasse, G. (1996). Luminescence and non-radiative processes in lanthanide squarate hydrates. Journal of Physics and Chemistry of Solids, 57(11), 1727-1734. doi:10.1016/0022-3697(96)00032-7He, R., Zhou, J., Fu, H., Zhang, S., & Jiang, C. (2018). Room-temperature in situ fabrication of Bi 2 O 3 /g-C 3 N 4 direct Z-scheme photocatalyst with enhanced photocatalytic activity. Applied Surface Science, 430, 273-282. doi:10.1016/j.apsusc.2017.07.191ZHANG, K., LIU, C., HUANG, F., ZHENG, C., & WANG, W. (2006). Study of the electronic structure and photocatalytic activity of the BiOCl photocatalyst. Applied Catalysis B: Environmental, 68(3-4), 125-129. doi:10.1016/j.apcatb.2006.08.002Corkett, A. J., Chen, Z., Bogdanovski, D., Slabon, A., & Dronskowski, R. (2019). Band Gap Tuning in Bismuth Oxide Carbodiimide Bi2O2NCN. Inorganic Chemistry, 58(9), 6467-6473. doi:10.1021/acs.inorgchem.9b0067

Control of lymphocyte shape and the chemotactic response by the GTP exchange factor Vav

7 FiguresRho GTPases control many facets of cell polarity and migration; namely, the reorganization of the cellular cytoskeleton to extracellular stimuli. Rho GTPases are activated by GTP exchange factors (GEFs), which induce guanosine diphosphate (GDP) release and the stabilization of the nucleotide-free state. Thus, the role of GEFs in the regulation of the cellular response to extracellular cues during cell migration is a critical step of this process. In this report, we have analyzed the activation and subcellular localization of the hematopoietic GEF Vav in human peripheral blood lymphocytes stimulated with the chemokine stromal cell–derived factor-1 (SDF-1α). We show a robust activation of Vav and its redistribution to motility-associated subcellular structures, and we provide biochemical evidence of the recruitment of Vav to the membrane of SDF-1α–activated human lymphocytes, where it transiently interacts with the SDF-1α receptor CXCR4. Overexpression of a dominant negative form of Vav abolished lymphocyte polarization, actin polymerization, and migration. SDF-1α–mediated cell polarization and migration also were impaired by overexpression of an active, oncogenic Vav, although the mechanism appears to be different. Together, our data postulate a pivotal role for Vav in the transmission of the migratory signal through the chemokine receptor CXCR4.From the Servicio de Inmunología, Hospital Universitario de la Princesa,Madrid, Spain; Centro de Investigación del Cáncer (CIC), Campus Miguel deUnamuno, Salamanca, Spain; and Facultad de Medicina, Universidad Autónoma de San Luis Potosí (UASLP), San Luis Potosí, Mexico.Peer reviewe

Physical activity and leisure habits and relation with Ruffier index in adolescents

El objetivo del estudio fue medir y correlacionar la práctica de actividad física y con el Índice de Ruffier (IR) en adolescentes. A un total de 884 alumnos (edad=16,4±0,8 años) se les midió la actividad física con la Versión modificada del Assessment of Physical Activity Level Questionnaire (APALQ) y se evaluó la capacidad de adaptación al esfuerzo mediante el Test Ruffier. La media del Índice de Ruffier fue 11,1±4,6 y el Índice de actividad física (IAF) 13,8±4,4. Las relaciones entre IAF y el IR, y entre horas de ocio sedentario e IR resultaron ser significativas aunque débiles (r=-0,31; p=0,000). En el IR los chicos presentaron valores superiores (t= -8,78; p= 0,000) a las chicas. También destinan más tiempo a la práctica de AF y estas diferencias fueron significativas en AF reglada y no reglada y en participación en competición (p=0,000), mientras que las chicas destinan más tiempo a actividades sedentarias como leer y estudiar (p=0,000). Es necesario promover la práctica de actividades físico-deportivas, especialmente entre las chicasThe aim of the study was to assess and correlate physical activity practice and fitness level in adolescents. A total of 884 students (age=16,4±0,8 years) answered the modified version of the “Assessment of Physical Activity Level Questionnaire (APALQ)” and aerobic capacity was assessed through the Ruffier Test. The mean Ruffier Index (IR) was 11,1±4,6 and the mean Physical Activity Index (IAF) was 13,8±4,4. The relationship between IAF and IR, and between sedentary activities in leisure time and IR, was significant (r=-0,31; p=0,000). although weak. Boys showed higher physical fitness values (t= -8,78; p= 0,000) and spent more time practicing physical activity. These differences were significant for both regulated and not regulated physical activity and for participation in competition (p=0.000). Girls spent more time in sedentary activities like reading and studying (p=0.000). It is necessary to promote physical activity and sport practice, especially among girls

Zeroth-order finite similitude and scaling of complex geometries in biomechanical experimentation

Scaled experimentation provides an alternative approach to full-scale biomechanical (and biological) testing but is known to suffer from scale effects, where the underlying system behaviour changes with scale. This phenomenon is arguably the overriding principal obstacle to the many advantages that scaled experimentation provides. These include reduced costs, materials and time, along with the eschewal of ethical compliance concerns with the application of substitute artificial materials as opposed to the use of hazardous biological agents. This paper examines the role scale effects play in biomechanical experimentation involving strain measurement and introduces a formulation that overtly captures scale dependencies arising from geometrical change. The basic idea underpinning the new scaling approach is the concept of space scaling, where a biomechanical experiment is scaled by the metaphysical mechanism of space contraction. The scaling approach is verified and validated with finite-element (FE) models and actual physical-trial experimentation using digital image correlation software applied to synthetic composite bone. The experimental design aspect of the approach allows for the selection of three-dimensional printing materials for trial-space analysis in a complex pelvis geometry. This aspect takes advantage of recent advancements in additive manufacturing technologies with the objective of countering behavioural distorting scale effects. Analysis is carried out using a laser confocal microscope to compare the trial and physical space materials and subsequently measured using surface roughness parameters. FE models were constructed for the left hemipelvis and results show similar strain patterns (average percentage error less than 10%) for two of the three trial-space material combinations. A Bland–Altman statistical analysis shows a good agreement between the FE models and physical experimentation and a good agreement between the physical-trial experimentation, providing good supporting evidence of the applicability of the new scaling approach in a wider range of experiments

B1 Was the Ancestor B Chromosome Variant in the Western Mediterranean Area in the Grasshopper Eyprepocnemis plorans.

We analyzed the distribution of 2 repetitive DNAs, i.e. ribosomal DNA (rDNA) and a satellite DNA (satDNA), on the B chromosomes found in 17 natural populations of the grasshopper Eyprepocnemis plorans plorans sampled around the western Mediterranean region, including the Iberian Peninsula, Balearic Islands, Sicily, and Tunisia. Based on the amount of these repetitive DNAs, 4 types of B variants were found: B 1 , showing an equal or higher amount of rDNA than satDNA, and 3 other variants, B 2 , B 24 and B 5 , bearing a higher amount of satDNA than rDNA. The variants B 1 and B 2 varied in size among populations: B 1 was about half the size of the X chromosome in Balearic Islands, but two-thirds of the X in Iberian populations at Alicante, Murcia and Albacete provinces. Likewise, B 2 was about one-third the size of the X chromosome in populations from the Granada province but half the size of the X in the populations collected at Málaga province. The widespread geographical distribution of the B 1 variant makes it the best candidate for being the ancestor B chromosome in the whole western Mediterranean region

Computerized model for the integration of data associated with the human brain

[EN]Our current work aims at compiling a computerized procedure that will allow different data sets to be integrated via the generation of a brain mapping system using the Linux operative system. This will provide a digitized model of the brain based on serial sections of the organ. The sections will be voxelized, thus obtaining spatial control of the images processed. The system will per mit the linking of specific brain areas to associated data bases, creating true spatial thematic maps. Our development includes the use of physical and logical computer elements that will allow th e co llectio n, management, an alysis, modulation, representation and output of data to brain territories

Specialized stellate cells offer a privileged route for rapid water flux in Drosophila renal tubule

Insects are highly successful, in part through an excellent ability to osmoregulate. The renal (Malpighian) tubules can secrete fluid faster on a per-cell basis than any other epithelium, but the route for these remarkable water fluxes has not been established. In Drosophila melanogaster, we show that 4 genes of the major intrinsic protein family are expressed at a very high level in the fly renal tissue: the aquaporins (AQPs) Drip and Prip and the aquaglyceroporins Eglp2 and Eglp4. As predicted from their structure, and by their transport function by expressing these proteins in Xenopus oocytes, Drip, Prip, and Eglp2 show significant and specific water permeability, whereas Eglp2 and Eglp4 show very high permeability to glycerol and urea. Knockdowns of any of these genes result in impaired hormone-induced fluid secretion. The Drosophila tubule has 2 main secretory cell types: active cation-transporting principal cells, wherein the aquaglyceroporins localize to opposite plasma membranes, and small stellate cells, the site of the chloride shunt conductance, with these AQPs localizing to opposite plasma membranes. This suggests a model in which osmotically obliged water flows through the stellate cells. Consistent with this model, fluorescently labeled dextran, an in vivo marker of membrane water permeability, is trapped in the basal infoldings of the stellate cells after kinin diuretic peptide stimulation, confirming that these cells provide the major route for transepithelial water flux. The spatial segregation of these components of epithelial water transport may help to explain the unique success of the higher insects in regulating their internal environments

Evaluación y análisis de propiedades estructurales de productos de madera

Wood products focused on construction are supported by standards for the evaluation of their properties and their quality control. Due to the specific characteristics of these products, specialized laboratories with suitable equipment and qualified people are necessary to value the obtained results. This paper shows the results of the evaluations conducted during the year 2012 about different structural properties of wood products for construction: plywoods, chipboards, deckings, glued laminated timber, and cross laminated timber. The conditions that affect their quality and fitness for use are discussed, providing to the industry the necessary steps to correct failures or to optimize products and design. Last, precise indications of usefulness are given for the end users of the products.Los productos de madera destinados a la construcción están dotados de normativa de apoyo para la evaluación de sus propiedades y el control y seguimiento de su calidad. Por las particularidades del material, es necesario disponer de laboratorios especializados que aporten el equipamiento adecuado para la ejecución de dichas tareas y de personal experimentado que valore correctamente los resultados obtenidos. En este trabajo se presentan los resultados de las evaluaciones desarrolladas durante el año 2012 sobre las propiedades estructurales en distintos productos de madera destinados a la construcción (tableros contrachapados, tableros de partículas, suelos de madera para exterior, madera laminada encolada y madera contralaminada) y se debate sobre los aspectos que afectan a su calidad y adecuación al uso, aportando a la industria las medidas necesarias para la corrección de fallos o la optimización del producto y su diseño, así como proporcionar indicaciones precisas a los usuarios de los productos