155 research outputs found
On the discovery of doubly-magic Ni
The paper reports on the first observation of doubly-magic Nickel-48 in an
experimental at the SISSI/LISE3 facility of GANIL. Four Nickel-48 isotopes were
identified. In addition, roughly 100 Nickel-49, 50 Iron-45, and 290 Chromium-42
isotopes were observed. This opens the possibility to search for two-proton
emission from these nuclei.Comment: 4 pages, 3 figures, accepted for publication in Phys. Rev. Let
Crossing the Dripline to 11N Using Elastic Resonance Scattering
The level structure of the unbound nucleus 11N has been studied by 10C+p
elastic resonance scattering in inverse geometry with the LISE3 spectrometer at
GANIL, using a 10C beam with an energy of 9.0 MeV/u. An additional measurement
was done at the A1200 spectrometer at MSU. The excitation function above the
10C+p threshold has been determined up to 5 MeV. A potential-model analysis
revealed three resonance states at energies 1.27 (+0.18-0.05) MeV (Gamma=1.44
+-0.2 MeV), 2.01(+0.15-0.05) MeV, (Gamma=0.84 +-$0.2 MeV) and 3.75(+-0.05) MeV,
(Gamma=0.60 +-0.05 MeV) with the spin-parity assignments I(pi) =1/2+, 1/2- and
5/2+, respectively. Hence, 11N is shown to have a ground state parity inversion
completely analogous to its mirror partner, 11Be. A narrow resonance in the
excitation function at 4.33 (+-0.05) MeV was also observed and assigned
spin-parity 3/2-.Comment: 14 pages, 9 figures, twocolumn Accepted for publication in PR
Interactive models of communication at the nanoscale using nanoparticles that talk to one another
[EN] 'Communication' between abiotic nanoscale chemical systems is an almost-unexplored field with enormous potential. Here we show the design and preparation of a chemical communication system based on enzyme-powered Janus nanoparticles, which mimics an interactive model of communication. Cargo delivery from one nanoparticle is governed by the biunivocal communication with another nanoparticle, which involves two enzymatic processes and the interchange of chemical messengers. The conceptual idea of establishing communication between nanodevices opens the opportunity to develop complex nanoscale systems capable of sharing information and cooperating.A. L.-L. is grateful to 'La Caixa' Banking Foundation for his PhD fellowship. We wish to thank the Spanish Government (MINECO Projects MAT2015-64139-C4-1, CTQ2014-58989-P and CTQ2015-71936-REDT and AGL2015-70235-C2-2-R) and the Generalitat Valenciana (Project PROMETEOII/2014/047) for support. The Comunidad de Madrid (S2013/MIT-3029, Programme NANOAVANSENS) is also gratefully acknowledged.Llopis-Lorente, A.; DĂez, P.; SĂĄnchez, A.; Marcos MartĂnez, MD.; SancenĂłn Galarza, F.; MartĂnez-Ruiz, P.; Villalonga, R.... (2017). Interactive models of communication at the nanoscale using nanoparticles that talk to one another. Nature Communications. 8:1-7. https://doi.org/10.1038/ncomms15511S178Tseng, R., Huang, J., Ouyang, J., Kaner, R. & Yang, Y. Polyaniline nanofiber/gold nanoparticle nonvolatile memory. Nano Lett. 5, 1077â1080 (2005).Liu, R. & Sen, A. Autonomous nanomotor based on copper-platinum segmented nanobattery. J. Am. Chem. Soc. 133, 20064â20067 (2011).Valov, I. et al. Nanobatteries in redox-based resistive switches require extension of memristor theory. Nat. Commun. 4, 1771 (2013).Tarn, D. et al. Mesoporous silica nanoparticle nanocarriers: biofunctionality and biocompatibility. Acc. Chem. Res. 46, 792â801 (2013).Kline, T. & Paxton, W. Catalytic nanomotors: remote-controlled autonomous movement of striped metallic nanorods. Angew. Chem. Int. Ed. 117, 754â756 (2005).Akyildiz, I. F., Brunetti, F. & BlĂĄzquez, C. Nanonetworks: a new communication paradigm. Comput. Netw. 52, 2260â2279 (2008).Suda, T., Moore, M., Nakano, T., Egashira, R. & Enomoto, A. Exploratory research on molecular communication between nanomachines. Nat. Comput. 25, 1â30 (2005).Malak, D. & Akan, O. B. Molecular communication nanonetworks inside human body. Nano Commun. Netw. 3, 19â35 (2012).Akyildiz, I. F., Jornet, J. M. & Pierobon, M. Nanonetworks: a new frontier in communications. Commun. ACM 54, 84â89 (2011).Nakano, T., Moore, M. J., Wei, F., Vasilakos, A. V. & Shuai, J. Molecular communication and networking: opportunities and challenges. IEEE Trans. Nanobiosci. 11, 135â148 (2012).Waters, C. M. & Bassler, B. L. Quorum sensing: cell-to-cell communication in bacteria. Annu. Rev. Cell Dev. Biol. 21, 319â346 (2005).Dickschat, J. S. Quorum sensing and bacterial biofilms. Nat. Prod. Rep. 27, 343â369 (2010).KerĂ©nyi, Ă., Bihary, D., Venturi, V. & Pongor, S. Stability of multispecies bacterial communities: signaling networks may stabilize microbiomes. PLoS ONE 8, e57947 (2013).Gotti, C. & Clementi, F. Neuronal nicotinic receptors: from structure to pathology. Prog. Neurobiol. 74, 363â396 (2004).Betke, K. M., Wells, C. A. & Hamm, H. E. GPCR mediated regulation of synaptic transmission. Prog. Neurobiol. 96, 304â321 (2012).Qian, L., Winfree, E. & Bruck, J. Neural network computation with DNA strand displacement cascades. Nature 475, 368â372 (2011).Benenson, Y. Biomolecular computing systems: principles, progress and potential. Nat. Rev. Genet. 13, 455â468 (2012).Ball, P. Chemistry meets computing. Nature 406, 118â120 (2000).de Silva, A. P. & McClenaghan, N. D. Molecular-Scale Logic Gates. Chem. Eur. J. 10, 574â586 (2004).Condon, A. Automata make antisense. Nature 429, 351â352 (2004).Seelig, G., Soloveichik, D., Zhang, D. Y. & Winfree, E. Enzyme-free nucleic acid logic circuits. Science 314, 1585â1588 (2006).Douglas, S. M., Bachelet, I. & Church, G. M. A logic-gated nanorobot for targeted transport of molecular payloads. Science 335, 831â834 (2012).Angelos, S., Yang, Y. W., Khashab, N. M., Stoddart, J. F. & Zink, J. I. Dual-controlled nanoparticles exhibiting AND logic. J. Am. Chem. Soc. 131, 11344â11346 (2009).Liu, H. et al. Dual-responsive surfaces modified with phenylboronic acid-containing polymer brush to reversibly capture and release cancer cells. J. Am. Chem. Soc. 135, 7603â7609 (2013).Lee, J. W. & Klajn, R. Dual-responsive nanoparticles that aggregate under the simultaneous action of light and CO2 . Chem. Commun. 51, 2036â2039 (2015).Liu, D. et al. Resettable, multi-readout logic gates based on controllably reversible aggregation of gold nanoparticles. Angew. Chem. Int. Ed. 50, 4103â4107 (2011).Chitode, J. S. Communication Theory Technical Publications (2010).Wood, J. T. Communication in Our Lives Wadsworth (2009).Guardado-Alvarez, T. M., Sudha Devi, L., Russell, M. M., Schwartz, B. J. & Zink, J. I. Activation of snap-top capped mesoporous silica nanocontainers using two near-infrared photons. J. Am. Chem. Soc. 135, 14000â14003 (2013).Baeza, A., Guisasola, E., Ruiz-HernĂĄndez, E. & Vallet-RegĂ, M. Magnetically triggered multidrug release by hybrid mesoporous silica nanoparticles. Chem. Mater. 24, 517â524 (2012).Zhang, Z. et al. Biocatalytic release of an anticancer drug from nucleic-acids-capped mesoporous SiO2 using DNA or molecular biomarkers as triggering stimuli. ACS Nano 7, 8455â8468 (2013).Tang, F., Li, L. & Chen, D. Mesoporous silica nanoparticles: synthesis, biocompatibility and drug delivery. Adv. Mater. 24, 1504â1534 (2012).Li, Z., Barnes, J. C., Bosoy, A., Stoddart, J. F. & Zink, J. I. Mesoporous silica nanoparticles in biomedical applications. Chem. Soc. Rev. 41, 2590â2605 (2012).Coll, C., Bernardos, A., MartĂnez-Måñez, R. & SancenĂłn, F. Gated silica mesoporous supports for controlled release and signaling applications. Acc. Chem. Res. 46, 339â349 (2013).Aznar, E. et al. Gated materials for on-command release of guest molecules. Chem. Rev. 116, 561â718 (2016).DĂez, P. et al. Toward the design of smart delivery systems controlled by integrated enzyme-based biocomputing ensembles. J. Am. Chem. Soc. 136, 9116â9123 (2014).Villalonga, R. et al. Enzyme-controlled sensing-actuating nanomachine based on Janus Au-mesoporous silica nanoparticles. Chem. Eur. J. 19, 7889â7894 (2013).Jerez, G., Kaufman, G., Prystai, M., Schenkeveld, S. & Donkor, K. K. Determination of thermodynamic pKa values of benzimidazole and benzimidazole derivatives by capillary electrophoresis. J. Sep. Sci. 32, 1087â1095 (2009).Sheffner, A. L. The reduction in vitro in viscosity of mucoprotein solutions by a new mucolytic agent, N-acetyl-L-cysteine. Ann. N. Y. Acad. Sci. 106, 298â310 (1963).Turkevich, J., Stevenson, P. C. & Hillier, J. A study of the nucleation and growth processes in the synthesis of colloidal gold. Discuss. Faraday Soc. 11, 55â75 (1951).Frens, G. Controlled Nucleation for the Regulation of the Particle Size in Monodisperse Gold Suspensions. Nature 241, 20â22 (1973).Yousef, F. O., Zughul, M. B. & Badwan, A. A. The modes of complexation of benzimidazole with aqueous ÎČ-cyclodextrin explored by phase solubility, potentiometric titration, 1H-NMR and molecular modeling studies. J. Incl. Phenom. Macrocycl. Chem. 57, 519â523 (2007).SĂĄnchez, A., DĂez, P., MartĂnez-RuĂz, P., Villalonga, R. & PingarrĂłn, J. M. Janus Au-mesoporous silica nanoparticles as electrochemical biorecognition-signaling system. Electrochem. Commun. 30, 51â54 (2013).Akyildiz, I. F., Pierobon, M., Balasubramaniam, S. & Koucheryavy, Y. The internet of Bio-Nano things. IEEE Commun. Mag. 53, 32â40 (2015).SancenĂłn, F., Pascual, L., Oroval, M., Aznar, E. & MartĂnez-Måñez, R. Gated silica mesoporous materials in sensing applications. ChemistryOpen 4, 418â437 (2015).Akyildiz, I. & Jornet, J. The Internet of nano-things. IEEE Wirel. Commun. 17, 58â63 (2010).GimĂ©nez, C. et al. Towards chemical communication between gated nanoparticles. Angew. Chem. Int. Ed. 53, 12629â12633 (2014).Davis, B. G., Lloyd, R. C. & Jones, J. B. Controlled site-selective glycosylation of proteins by a combined site-directed mutagenesis and chemical modification approach. J. Org. Chem. 63, 9614â9615 (1998)
Biomolecular Filters for Improved Separation of Output Signals in Enzyme Logic Systems Applied to Biomedical Analysis
Biomolecular logic systems processing biochemical input signals and producing
"digital" outputs in the form of YES/NO were developed for analysis of
physiological conditions characteristic of liver injury, soft tissue injury and
abdominal trauma. Injury biomarkers were used as input signals for activating
the logic systems. Their normal physiological concentrations were defined as
logic-0 level, while their pathologically elevated concentrations were defined
as logic-1 values. Since the input concentrations applied as logic 0 and 1
values were not sufficiently different, the output signals being at low and
high values (0, 1 outputs) were separated with a short gap making their
discrimination difficult. Coupled enzymatic reactions functioning as a
biomolecular signal processing system with a built-in filter property were
developed. The filter process involves a partial back-conversion of the
optical-output-signal-yielding product, but only at its low concentrations,
thus allowing the proper discrimination between 0 and 1 output values
Charge Transport in DNA-Based Devices
Charge migration along DNA molecules has attracted scientific interest for
over half a century. Reports on possible high rates of charge transfer between
donor and acceptor through the DNA, obtained in the last decade from solution
chemistry experiments on large numbers of molecules, triggered a series of
direct electrical transport measurements through DNA single molecules, bundles
and networks. These measurements are reviewed and presented here. From these
experiments we conclude that electrical transport is feasible in short DNA
molecules, in bundles and networks, but blocked in long single molecules that
are attached to surfaces. The experimental background is complemented by an
account of the theoretical/computational schemes that are applied to study the
electronic and transport properties of DNA-based nanowires. Examples of
selected applications are given, to show the capabilities and limits of current
theoretical approaches to accurately describe the wires, interpret the
transport measurements, and predict suitable strategies to enhance the
conductivity of DNA nanostructures.Comment: A single pdf file of 52 pages, containing the text and 23 figures.
Review about direct measurements of DNA conductivity and related theoretical
studies. For higher-resolution figures contact the authors or retrieve the
original publications cited in the caption
Realization and Properties of Biochemical-Computing Biocatalytic XOR Gate Based on Enzyme Inhibition by a Substrate
We consider a realization of the XOR logic gate in a process biocatalyzed by
an enzyme (here horseradish peroxidase: HRP), the function of which can be
inhibited by a substrate (hydrogen peroxide for HRP), when the latter is
inputted at large enough concentrations. A model is developed for describing
such systems in an approach suitable for evaluation of the analog noise
amplification properties of the gate. The obtained data are fitted for gate
quality evaluation within the developed model, and we discuss aspects of
devising XOR gates for functioning in "biocomputing" systems utilizing
biomolecules for information processing
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