Interaction of molecular and atomic hydrogen with (5,5) and (6,6) single-wall carbon nanotubes

Density functional theory has been used to study the interaction of molecular and atomic hydrogen with (5,5) and (6,6) single-wall carbon nanotubes. Static calculations allowing for different degrees of structural relaxation are performed, in addition to dynamical simulations. Molecular physisorption inside and outside the nanotube walls is predicted to be the most stable state of those systems. The binding energies for physisorption of the H2 molecule outside the nanotube are in the range 0.04–0.07 eV. This means that uptake and release of molecular hydrogen from nanotubes is a relatively easy process, as many experiments have proved. A chemisorption state, with the molecule dissociated and the two hydrogen atoms bonded to neighbor carbon atoms, has also been found. However, reaching this dissociative chemisorption state for an incoming molecule, or starting from the physisorbed molecule, is difficult because of the existence of a substantial activation barrier. The dissociative chemisorption deforms the tube and weakens the C-C bond. This effect can catalyze the shattering and scission of the tube by incoming hydrogen molecules with sufficient kinetic energy.This work was supported by DGESIC (Grant No. PB98-0345) and European Community (RTN-COMELCAN). We acknowledge the computational facilities provided by CESCA and CEPBA.Peer reviewe

Modulating charge carrier density and mobility in doped graphene by covalent functionalization

[EN] Covalent B-functionalization of B-doped graphene has been performed for the first time. The electronic properties and Hall effect of functionalized N- and B-doped graphene can be tuned by tailoring the electron-donating/-withdrawing properties of the organic addend.The authors appreciate support from the Ministerio de Economia y Competitividad (MINECO) of Spain (projects CTQ2015-69153-CO2-1, CTQ2016-79189-R and MAT2015-69669-P) and the Junta de Comunidades de Castilla-La Mancha (project SBPLY/17/180501/000254). L. M. A. thanks MINECO (CTQ2016-79189-R) for a doctoral FPI grant.Arellano, LM.; Yue, S.; Atienzar Corvillo, PE.; Gómez-Escalonilla, MJ.; Ortega Higueruelo, FJ.; Fierro, JLG.; García Gómez, H.... (2019). Modulating charge carrier density and mobility in doped graphene by covalent functionalization. Chemical Communications. 55(67):9999-10002. https://doi.org/10.1039/c9cc04571fS9999100025567Wang, X., Sun, G., Routh, P., Kim, D.-H., Huang, W., & Chen, P. (2014). Heteroatom-doped graphene materials: syntheses, properties and applications. Chem. Soc. Rev., 43(20), 7067-7098. doi:10.1039/c4cs00141aLavorato, C., Primo, A., Molinari, R., & Garcia, H. (2013). N-Doped Graphene Derived from Biomass as a Visible-Light Photocatalyst for Hydrogen Generation from Water/Methanol Mixtures. Chemistry - A European Journal, 20(1), 187-194. doi:10.1002/chem.201303689Latorre-Sánchez, M., Primo, A., & García, H. (2013). P-Doped Graphene Obtained by Pyrolysis of Modified Alginate as a Photocatalyst for Hydrogen Generation from Water-Methanol Mixtures. Angewandte Chemie International Edition, 52(45), 11813-11816. doi:10.1002/anie.201304505Duan, J., Chen, S., Jaroniec, M., & Qiao, S. Z. (2015). Heteroatom-Doped Graphene-Based Materials for Energy-Relevant Electrocatalytic Processes. ACS Catalysis, 5(9), 5207-5234. doi:10.1021/acscatal.5b00991Putri, L. K., Ong, W.-J., Chang, W. S., & Chai, S.-P. (2015). Heteroatom doped graphene in photocatalysis: A review. Applied Surface Science, 358, 2-14. doi:10.1016/j.apsusc.2015.08.177Niu, L., Li, Z., Hong, W., Sun, J., Wang, Z., Ma, L., … Yang, S. (2013). Pyrolytic synthesis of boron-doped graphene and its application as electrode material for supercapacitors. Electrochimica Acta, 108, 666-673. doi:10.1016/j.electacta.2013.07.025Sahoo, M., Sreena, K. P., Vinayan, B. P., & Ramaprabhu, S. (2015). Green synthesis of boron doped graphene and its application as high performance anode material in Li ion battery. Materials Research Bulletin, 61, 383-390. doi:10.1016/j.materresbull.2014.10.049Khai, T. V., Na, H. G., Kwak, D. S., Kwon, Y. J., Ham, H., Shim, K. B., & Kim, H. W. (2012). Comparison study of structural and optical properties of boron-doped and undoped graphene oxide films. Chemical Engineering Journal, 211-212, 369-377. doi:10.1016/j.cej.2012.09.081Osumi, S., Saito, S., Dou, C., Matsuo, K., Kume, K., Yoshikawa, H., … Yamaguchi, S. (2016). Boron-doped nanographene: Lewis acidity, redox properties, and battery electrode performance. Chemical Science, 7(1), 219-227. doi:10.1039/c5sc02246kXu, Q., Jiang, X., Zhu, W., Chen, C., Hu, G., & Li, Q. (2016). Synthesis, preliminary biological evaluation and 3D-QSAR study of novel 1,5-disubstituted-2(1H)-pyridone derivatives as potential anti-lung cancer agents. Arabian Journal of Chemistry, 9(5), 721-735. doi:10.1016/j.arabjc.2015.08.001Pimenta, M. A., Dresselhaus, G., Dresselhaus, M. S., Cançado, L. G., Jorio, A., & Saito, R. (2007). Studying disorder in graphite-based systems by Raman spectroscopy. Phys. Chem. Chem. Phys., 9(11), 1276-1290. doi:10.1039/b613962kVoggu, R., Rout, C. S., Franklin, A. D., Fisher, T. S., & Rao, C. N. R. (2008). Extraordinary Sensitivity of the Electronic Structure and Properties of Single-Walled Carbon Nanotubes to Molecular Charge-Transfer. The Journal of Physical Chemistry C, 112(34), 13053-13056. doi:10.1021/jp805136eBiswal, M., Zhang, X., Schilter, D., Lee, T. K., Hwang, D. Y., Saxena, M., … Ruoff, R. S. (2017). Sodide and Organic Halides Effect Covalent Functionalization of Single-Layer and Bilayer Graphene. Journal of the American Chemical Society, 139(11), 4202-4210. doi:10.1021/jacs.7b00932Vizuete, M., Gómez-Escalonilla, M. J., Fierro, J. L. G., Ohkubo, K., Fukuzumi, S., Yudasaka, M., … Langa, F. (2014). Photoinduced electron transfer in a carbon nanohorn–C60 conjugate. Chemical Science, 5(5), 2072. doi:10.1039/c3sc53342eAllongue, P., Delamar, M., Desbat, B., Fagebaume, O., Hitmi, R., Pinson, J., & Savéant, J.-M. (1997). Covalent Modification of Carbon Surfaces by Aryl Radicals Generated from the Electrochemical Reduction of Diazonium Salts. Journal of the American Chemical Society, 119(1), 201-207. doi:10.1021/ja963354sBarrejón, M., Gómez-Escalonilla, M. J., Fierro, J. L. G., Prieto, P., Carrillo, J. R., Rodríguez, A. M., … Langa, F. (2016). Modulation of the exfoliated graphene work function through cycloaddition of nitrile imines. Physical Chemistry Chemical Physics, 18(42), 29582-29590. doi:10.1039/c6cp05285aBarrejón, M., Primo, A., Gómez-Escalonilla, M. J., Fierro, J. L. G., García, H., & Langa, F. (2015). Covalent functionalization of N-doped graphene by N-alkylation. Chemical Communications, 51(95), 16916-16919. doi:10.1039/c5cc06285cSu, C.-Y., Xu, Y., Zhang, W., Zhao, J., Tang, X., Tsai, C.-H., & Li, L.-J. (2009). Electrical and Spectroscopic Characterizations of Ultra-Large Reduced Graphene Oxide Monolayers. Chemistry of Materials, 21(23), 5674-5680. doi:10.1021/cm902182

Unprecedented pathway of reducing equivalents in a diflavin-linked disulfide oxidoreductase

Flavoproteinsparticipateinawidevarietyofphysiologicallyrelevant processes that typically involve redox reactions. Within this protein superfamily, there exists a group that is able to transfer reducing equivalents from FAD to a redox-active disulfide bridge, which further reduces disulfide bridges in target proteins to regulate their structure and function. We have identified a previously undescribed type of flavin enzyme that is exclusive to oxygenic photosynthetic prokaryotes and that is based on the primary sequence that had been assigned as an NADPH-dependent thioredoxin reductase (NTR). However, our experimental data show that the protein does not transfer reducing equivalents from flavins to disulfides as in NTRs but functions in the opposite direction. High-resolution structures of the protein from Gloeobacter violaceus and Synechocystis sp. PCC6803 obtained by X-ray crystallography showed two juxtaposed FADmoleculespermonomerinredoxcommunicationwithanactive disulfide bridge in a variant of the fold adopted by NTRs. We have tentatively named the flavoprotein “DDOR” (diflavin-linked disulfide oxidoreductase) and propose that its activity is linked to a thiol-basedtransferofreducingequivalentsinbacterialmembranes. These findings expand the structural and mechanistic repertoire of flavoenzymes with oxidoreductase activity and pave the way to explore new protein engineering approaches aimed at designing redox-active proteins for diverse biotechnological applications.Spanish Ministerio de Economía, Industria y Competitividad BFU2016-80343-P, BIO2016-75634-

Viologen-functionalized single-walled carbon nanotubes as carrier nanotags for electrochemical immunosensing. Application to TGF-β1 cytokine

Viologen-SWCNT hybrids are synthesized by aryl-diazonium chemistry in the presence of isoamyl nitrite followed by condensation reaction of the resulting HOOC-PheSWCNT with 1-(3-aminoethyl)-4,4’-bipyridinium bromine and N-alkylation with 2- bromoethylamine. The V-Phe-SWCNT hybrids were characterized by using different spectroscopic techniques (FT-IR, Raman, UV-vis), TGA and Kaiser test. ViologenSWCNTs were used for the preparation of an electrochemical immunosensor for the determination of the transforming growth factor β1 (TGF-β1) cytokine considered as a reliable biomarker in several human diseases. The methodology involved preparation of VPhe-SWCNT(-HRP)-anti-TGF conjugates by covalent linkage of HRP and anti-TGF onto V-Phe-SWCNT hybrids. Biotinylated anti-TGF antibodies were immobilized onto 4- carboxyphenyl-functionalized SPCEs modified with streptavidin and a sandwich type 2 immunoassay was implemented for TGF-β1 with signal amplification using V-PheSWCNT(-HRP)-anti-TGF conjugates as carrier tags. The analytical characteristics exhibited by the as prepared immunosensor (range of linearity between 2.5 and 1000 pg mL-1 TGF-β1; detection limit of 0.95 pg mL-1 ) improve notably those reported with other previous immunosensors or ELISA kits. A great selectivity against other proteins was also found. The prepared immunosensor was validated by determining TGF-β1 in real saliva samples. Minimal sample treatment was required and the obtained results were in excellent agreement with those obtained by using a commercial ELISA kit

Longitudinal dynamics of SARS-CoV-2-specific cellular and humoral immunity after natural infection or BNT162b2 vaccination

The timing of the development of specific adaptive immunity after natural SARS-CoV-2 infection, and its relevance in clinical outcome, has not been characterized in depth. Description of the long-term maintenance of both cellular and humoral responses elicited by real-world anti-SARS-CoV-2 vaccination is still scarce. Here we aimed to understand the development of optimal protective responses after SARS-CoV-2 infection and vaccination. We performed an early, longitudinal study of S1-, M- and N-specific IFN-γ and IL-2 T cell immunity and anti-S total and neutralizing antibodies in 88 mild, moderate or severe acute COVID-19 patients. Moreover, SARS-CoV-2-specific adaptive immunity was also analysed in 234 COVID-19 recovered subjects, 28 uninfected BNT162b2-vaccinees and 30 uninfected healthy controls. Upon natural infection, cellular and humoral responses were early and coordinated in mild patients, while weak and inconsistent in severe patients. The S1-specific cellular response measured at hospital arrival was an independent predictive factor against severity. In COVID-19 recovered patients, four to seven months post-infection, cellular immunity was maintained but antibodies and neutralization capacity declined. Finally, a robust Th1-driven immune response was developed in uninfected BNT162b2-vaccinees. Three months post-vaccination, the cellular response was comparable, while the humoral response was consistently stronger, to that measured in COVID-19 recovered patients. Thus, measurement of both humoral and cellular responses provides information on prognosis and protection from infection, which may add value for individual and public health recommendations

Monitoring treatment of vocal fold paralysis by biomechanical analysis of voice

A case study of vocal fold paralysis treatment is described with the help of the voice quality analysis application BioMet®Phon. The case corresponds to a description of a 40 - year old female patient who was diagnosed of vocal fold paralysis following a cardio - pulmonar intervention which required intubation for 8 days and posterior tracheotomy for 15 days. The patient presented breathy and asthenic phon ation, and dysphagia. Six main examinations were conducted during a full year period that the treatment lasted consisting in periodic reviews including video - endostroboscopy, voice analysis and breathing function monitoring. The phoniatrician treatment inc luded 20 sessions of vocal rehabilitation, followed by an intracordal infiltration with Radiesse 8 months after the rehabilitation treatment started followed by 6 sessions of rehabilitation more. The videondoscopy and the voicing quality analysis refer a s ubstantial improvement in the vocal function with recovery in all the measures estimated (jitter, shimmer, mucosal wave contents, glottal closure, harmonic contents and biomechanical function analysis). The paper refers the procedure followed and the results obtained by comparing the longitudinal progression of the treatment, illustrating the utility of voice quality analysis tools in speech therapy

Human Rickettsia felis Infection, Canary Islands, Spain

We report the first cases of human infection by Rickettsia felis in the Canary Islands. Antibodies against R. felis were found in 5 adsorbed serum samples from 44 patients with clinically suspected rickettsiosis by Western blot serology. Fleas from 1 patient's dog were positive for R. felis by polymerase chain reaction

Actas III Congreso Internacional Pobreza y Hambre: Educación y tecnología en el contexto de la pandemia

En el presente volumen publicamos las actas del III Congreso Internacional «Pobreza y Hambre: Educación y Tecnología en el contexto de la pandemia» celebrado en Valencia, durante los días 9 y 10 de noviembre de 2021. En este documento quedan recogidas las intervenciones y ponencias que conformaron el citado congreso, así como las diversas contribuciones, transcripciones, síntesis de mesas de expertos y artículos que dan cuenta de la amplia labor realizada y de la puesta en común que sobre la misma llevaron a cabo los investigadores de la Cátedra de la Caridad de la UCV en el contexto de la pandemia originada por la irrupción del virus SARS/CoV2 en nuestras vidas.Cátedra de la Caridad Santo Tomás de VillanuevaHumanidade

Formation and Photoinduced Electron Transfer in Porphyrin- and Phthalocyanine-Bearing N-Doped Graphene Hybrids Synthesized by Click Chemistry

Graphene doped with heteroatoms such as nitrogen, boron, and phosphorous by replacing some of the skeletal carbon atoms is emerging as an important class of two-dimensional materials as it offers the much-needed bandgap for optoelectronic applications and provides better access for chemical functionalization at the heteroatom sites. Covalent grafting of photosensitizers onto such doped graphenes makes them extremely useful for light-induced applications. Herein, we report the covalent functionalization of N-doped graphene (NG) with two well-known electron donor photosensitizers, namely, zinc porphyrin (ZnP) and zinc phthalocyanine (ZnPc), using the simple click chemistry approach. Covalent attachment of ZnP and ZnPc at the N-sites of NG in NG−ZnP and NG−ZnPc hybrids was confirmed by using a range of spectroscopic, thermogravimetric and imaging techniques. Ground- and excited-state interactions in NG−ZnP and NG−ZnPc were monitored by using spectral and electrochemical techniques. Efficient quenching of photosensitizer fluorescence in these hybrids was observed, and the relatively easier oxidations of ZnP and ZnPc supported excited-state charge-separation events. Photoinduced charge separation in NG−ZnP and NG−ZnPc hybrids was confirmed by using the ultrafast pump-probe technique. The measured rate constants were of the order of 1010 s,−1 thus indicating ultrafast electron transfer phenomena

Assessment of a New ROS1 Immunohistochemistry Clone (SP384) for the Identification of ROS1 Rearrangements in Patients with Non–Small Cell Lung Carcinoma: the ROSING Study

Introduction: The ROS1 gene rearrangement has become an important biomarker in NSCLC. The College of American Pathologists/International Association for the Study of Lung Cancer/Association for Molecular Pathology testing guidelines support the use of ROS1 immunohistochemistry (IHC) as a screening test, followed by confirmation with fluorescence in situ hybridization (FISH) or a molecular test in all positive results. We have evaluated a novel anti-ROS1 IHC antibody (SP384) in a large multicenter series to obtain real-world data. Methods: A total of 43 ROS1 FISH-positive and 193 ROS1 FISH-negative NSCLC samples were studied. All specimens were screened by using two antibodies (clone D4D6 from Cell Signaling Technology and clone SP384 from Ventana Medical Systems), and the different interpretation criteria were compared with break-apart FISH (Vysis). FISH-positive samples were also analyzed with next-generation sequencing (Oncomine Dx Target Test Panel, Thermo Fisher Scientific). Results: An H-score of 150 or higher or the presence of at least 70% of tumor cells with an intensity of staining of 2+ or higher by the SP384 clone was the optimal cutoff value (both with 93% sensitivity and 100% specificity). The D4D6 clone showed similar results, with an H-score of at least 100 (91% sensitivity and 100% specificity). ROS1 expression in normal lung was more frequent with use of the SP384 clone (p < 0.0001). The ezrin gene (EZR)-ROS1 variant was associated with membranous staining and an isolated green signal FISH pattern (p = 0.001 and p = 0.017, respectively). Conclusions: The new SP384 ROS1 IHC clone showed excellent sensitivity without compromising specificity, so it is another excellent analytical option for the proposed testing algorithm