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Alekseev A, Lane J, Li Y. The U( n) Gelfand-Zeitlin system as a tropical limit of Ginzburg-Weinstein diffeomorphisms. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2018; 376:rsta.2017.0428. [PMID: 30224420 PMCID: PMC6158378 DOI: 10.1098/rsta.2017.0428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
In this paper, we show that the Ginzburg-Weinstein diffeomorphism [Formula: see text] of Alekseev & Meinrenken (Alekseev, Meinrenken 2007 J. Differential Geom.76, 1-34. (10.4310/jdg/1180135664)) admits a scaling tropical limit on an open dense subset of [Formula: see text] The target of the limit map is a product [Formula: see text], where [Formula: see text] is the interior of a cone, T is a torus, and [Formula: see text] carries an integrable system with natural action-angle coordinates. The pull-back of these coordinates to [Formula: see text] recovers the Gelfand-Zeitlin integrable system of Guillemin & Sternberg (Guillemin, Sternberg 1983 J. Funct. Anal.52, 106-128. (10.1016/0022-1236(83)90092-7)). As a by-product of our proof, we show that the Lagrangian tori of the Flaschka-Ratiu integrable system on the set of upper triangular matrices meet the set of totally positive matrices for sufficiently large action coordinates.This article is part of the theme issue 'Finite dimensional integrable systems: new trends and methods'.
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Kurskaya O, Sobolev I, Murashkina T, Alekseev A, Sharshov K, Shestopalov A. Etiology of acute respiratory infections in hospitalized children in Novosibirsk, Russia, in 2013–2017. Int J Infect Dis 2018. [PMCID: PMC7172087 DOI: 10.1016/j.ijid.2018.04.4258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Alekseev A, Arslanova D, Belyakov V, Bessette D, Gornikel I, Kalinin V, Kaparkova M, Mitchell N, Serio L, Shatil N, Sytchevsky S, Vasiliev V. Control strategy for mitigation of pulsed heat load transferred to ITER cryoplant from magnets. FUSION ENGINEERING AND DESIGN 2017. [DOI: 10.1016/j.fusengdes.2017.05.092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Prokopyeva E, Romanovskaya A, Sharshov K, Sobolev I, Alekseev A, Durymanov A, Shestopalov A. Molecular determinants possibly involved in the adaptation of pandemic A(H1N1)09 influenza virus to a new host. Future Virol 2017. [DOI: 10.2217/fvl-2017-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aim: To determine the molecular basis of A(H1N1)pdm09 virus adaptation to a new host. Methods: The pandemic virus A/Russia/01/2009 was adapted to mice by serial lung-to-lung passages. The growth properties, pathogenicity and genome sequences of the mouse-adapted virus were compared with those of the parental strain. Results: The A(H1N1)pdm09 virus caused mouse death after only six lung-to-lung passages. Mutations in the influenza virus antigen were found in the brain, liver, kidney and in intestine by immunohistochemistry. Conclusion: Our findings suggest that multiple mutations in the viral genome promote rapid adaptation of the A(H1N1)pdm09 virus and cause generalized infection in mice.
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Gulyaeva M, Sharshov K, Suzuki M, Sobolev I, Sakoda Y, Alekseev A, Sivay M, Shestopalova L, Shchelkanov M, Shestopalov A. Genetic characterization of an H2N2 influenza virus isolated from a muskrat in Western Siberia. J Vet Med Sci 2017; 79:1461-1465. [PMID: 28690288 PMCID: PMC5573837 DOI: 10.1292/jvms.17-0048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Thirty-two muskrats (Ondatra zibethicus) were captured for surveillance
of avian influenza virus in wild waterfowl and mammals near Lake Chany, Western Siberia,
Russia. A/muskrat/Russia/63/2014 (H2N2) was isolated from an apparently healthy muskrat
using chicken embryos. Based on phylogenetic analysis, the hemagglutinin and neuraminidase
genes of this isolate were classified into the Eurasian avian-like influenza virus clade
and closely related to low pathogenic avian influenza viruses (LPAIVs) isolated from wild
water birds in Italy and Sweden, respectively. Other internal genes were also closely
related to LPAIVs isolated from Eurasian wild water birds. Results suggest that
interspecies transmission of LPAIVs from wild water birds to semiaquatic mammals occurs,
facilitating the spread and evolution of LPAIVs in wetland areas of Western Siberia.
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Preuster P, Alekseev A, Wasserscheid P. Hydrogen Storage Technologies for Future Energy Systems. Annu Rev Chem Biomol Eng 2017; 8:445-471. [DOI: 10.1146/annurev-chembioeng-060816-101334] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Future energy systems will be determined by the increasing relevance of solar and wind energy. Crude oil and gas prices are expected to increase in the long run, and penalties for CO2 emissions will become a relevant economic factor. Solar- and wind-powered electricity will become significantly cheaper, such that hydrogen produced from electrolysis will be competitively priced against hydrogen manufactured from natural gas. However, to handle the unsteadiness of system input from fluctuating energy sources, energy storage technologies that cover the full scale of power (in megawatts) and energy storage amounts (in megawatt hours) are required. Hydrogen, in particular, is a promising secondary energy vector for storing, transporting, and distributing large and very large amounts of energy at the gigawatt-hour and terawatt-hour scales. However, we also discuss energy storage at the 120–200-kWh scale, for example, for onboard hydrogen storage in fuel cell vehicles using compressed hydrogen storage. This article focuses on the characteristics and development potential of hydrogen storage technologies in light of such a changing energy system and its related challenges. Technological factors that influence the dynamics, flexibility, and operating costs of unsteady operation are therefore highlighted in particular. Moreover, the potential for using renewable hydrogen in the mobility sector, industrial production, and the heat market is discussed, as this potential may determine to a significant extent the future economic value of hydrogen storage technology as it applies to other industries. This evaluation elucidates known and well-established options for hydrogen storage and may guide the development and direction of newer, less developed technologies.
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Rupchev G, Alekseev A, Tkhostov A, Spivakovskaya A, Guldan V. The peculiarity of Experiencing Body by Patients in Schizophrenia. Eur Psychiatry 2017. [DOI: 10.1016/j.eurpsy.2017.02.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
IntroductionBy the present, the study of corporeality as a psychological phenomenon in schizophrenia has had a lack of attention. At the focus of works, there have been mainly psychopathological phenomena: cenestopathies, visceral hallucinations and body scheme disturbances. There is an evidence of the necessity for psychological investigations: the execution of radical changes in appearance, a frequent turning to plastic surgery, dysfunctional wearing and transsexuality.ObjectivesThe experimental group consisted of 23 patients in schizophrenia of paranoid type (F 20.00). The control group consisted of 27 healthy subjects.AimIt is to study the peculiarity of experiencing their own body by patients in schizophrenia.MethodsThere are projective techniques, such as: “A Picture of Me”, “Verbal Self-Portrait”, ‘A Picture of Inner Body” and the psychosemantic test “Classification of Sensations”.ResultsThere are statistically significant differences (P < 0.005) found between the groups:– patients with schizophrenia are characterized for their deficit of experiencing their body. It does not refer to “Myself” and is deinvidualized. The body does not serve as a physical presentation of the subject in a social world;– a wary attitude is observed in relation to body displays in the form of inner body sensations with a minor (than in norm) awareness relatively to the inner arrangement of their own body. This causes the increase of the quantity of intraceptive sensations categorized by patients in schizophrenia as unhealthy or a threat.ConclusionThe above-mentioned peculiar features of corporeality in schizophrenia make it a source of negative experiences.Disclosure of interestThe authors have not supplied their declaration of competing interest.
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Rupchev G, Alekseev A, Morozova M, Kaleda V, Tkhostov A, Tikhonov D, Listova A. Executive Function Assessment in Young Hospitalized Schizophrenic Patients with the “CANTAB Schizophrenia Battery” (Russian Sample). Eur Psychiatry 2017. [DOI: 10.1016/j.eurpsy.2017.02.119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
IntroductionImpairment of executive function is the fundamental feature of the cognitive dysfunction in schizophrenia has to be measured throughout the illness regularly. Computerized technologies for assessment of cognitive dysfunction are widely used. However, their applicability in hospitalized schizophrenic patients setting should be specially examined.ObjectiveExecutive function in schizophrenia.AimsTo test the applicability of “CANTAB” neurocognitive battery for measurement of executive function in young hospitalized schizophrenic patients in Russian sample.MethodsFifteen inpatients diagnosed with schizophrenia according to ICD-10 (F 20.хх), 13 males and 2 females, aged 23.5(SD 3.2), disease duration is 5(SD 1.6) years and 16 healthy individuals, 7 males and 9 females, aged 21.3(SD 0.7). Spatial Working Memory (SWM) (Mnemonic Executive function), Stockings of Cambridge (OTS) (Planning Executive function), Intra/Extra-Dimensional Shift (IED) (Cognitive flexibility) were administered.ResultsThe majority of patients and controls easily understood the test instructions. Both groups did not have any difficulties with the touchpad. The “CANTAB” demonstrated sensitivity to the impairments of executive function. As a group, patients with schizophrenia performed significantly worse than controls on almost all tests: SWM–Between errors (P = 0.028), Total errors (P = 0.019), Strategy (P = 0.03), Mean time to last response (P = 0.001); OTS–Mean choices to correct (P = 0.044), Problems solved on first choice (P = 0.009), Probability of error given correct (P = 0.021); IED–Total errors (P = 0.015), Total trials (P = 0.002).ConclusionThe “CANTAB” is an applicable instrument for assessment of the executive function in young hospitalized schizophrenic patients. It can be used both for experimental and clinical needs.Disclosure of interestThe authors have not supplied their declaration of competing interest.
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Chernykh E, Kharintsev S, Fishman A, Alekseev A, Salakhov M. Determination of the Glass Transition Temperature of Freestanding and Supported Azo-Polymer Thin Films by Thermal Assisted Atomic Force Microscopy. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201713900007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Lee DH, Sharshov K, Swayne DE, Kurskaya O, Sobolev I, Kabilov M, Alekseev A, Irza V, Shestopalov A. Novel Reassortant Clade 2.3.4.4 Avian Influenza A(H5N8) Virus in Wild Aquatic Birds, Russia, 2016. Emerg Infect Dis 2017; 23:359-360. [PMID: 27875109 PMCID: PMC5324796 DOI: 10.3201/eid2302.161252] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The emergence of novel avian influenza viruses in migratory birds is of concern because of the potential for virus dissemination during fall migration. We report the identification of novel highly pathogenic avian influenza viruses of subtype H5N8, clade 2.3.4.4, and their reassortment with other avian influenza viruses in waterfowl and shorebirds of Siberia.
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Kharintsev S, Alekseev A, Loos J. Etchant-based design of gold tip apexes for plasmon-enhanced Raman spectromicroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 171:139-143. [PMID: 27501486 DOI: 10.1016/j.saa.2016.07.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 07/22/2016] [Accepted: 07/31/2016] [Indexed: 06/06/2023]
Abstract
In this paper, we gain insight into the design and optimization of plasmonic (metallic) tips prepared with dc-pulsed voltage electrochemical etching gold wires, provided that, a duty cycle is self-tuned. Physically, it means that etching electrolyte attacks the gold wire equally for all pulse lengths, regardless of its surface shape. Etchant effect on the reproducibility of a curvature radius of the tip apex is demonstrated. It means that the gold conical tips can be designed chemically with a choice of proper etchant electrolyte. It is suggested to use a microtomed binary polymer blend consisting of polyamide and low density polyethylene, as a calibration grating, for optimizing and standardizing tip-enhanced Raman scattering performance.
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Martinez JM, Alekseev A, Sborchia C, Choi C, Utin Y, Jun C, Terasawa A, Popova E, Xiang B, Sannazaro G, Lee A, Martin A, Teissier P, Sabourin F, Caixas J, Fernandez E, Zarzalejos J, Kim HS, Kim Y, Privalova E, Du S, Wang S, Albin V, Gaucher T, Borrelly S, Cambazar M, Sfarni S. ITER vacuum vessel structural analysis completion during manufacturing phase. FUSION ENGINEERING AND DESIGN 2016. [DOI: 10.1016/j.fusengdes.2016.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Utin Y, Alekseev A, Sborchia C, Choi C, Albin V, Barabash V, Davis J, Fabritsiev S, Giraud B, Guirao J, Koenig W, Kedrov I, Kuzmin E, Levesy B, Martinez JM, Prebeck M, Privalova E, Ranzinger F, Savrukhin P, Schiller T, Sfarni S, Valenta L, Umprecht J. Starting manufacturing phase of ITER upper ports. FUSION ENGINEERING AND DESIGN 2015. [DOI: 10.1016/j.fusengdes.2015.06.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Martinez JM, Jun CH, Portafaix C, Alekseev A, Sborchia C, Choi CH, Albin V, Borrelly S, Cambazar M, Gaucher T, Sfarni S, Tailhardat O. Structural damages prevention of the ITER vacuum vessel and ports by elasto-plastic analysis with regards to RCC-MR. FUSION ENGINEERING AND DESIGN 2015. [DOI: 10.1016/j.fusengdes.2015.06.159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Hedley GJ, Ward AJ, Alekseev A, Howells CT, Martins ER, Serrano LA, Cooke G, Ruseckas A, Samuel IDW. Determining the optimum morphology in high-performance polymer-fullerene organic photovoltaic cells. Nat Commun 2014; 4:2867. [PMID: 24343223 PMCID: PMC3905772 DOI: 10.1038/ncomms3867] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 11/05/2013] [Indexed: 11/17/2022] Open
Abstract
The morphology of bulk heterojunction organic photovoltaic cells controls many of the performance characteristics of devices. However, measuring this morphology is challenging because of the small length-scales and low contrast between organic materials. Here we use nanoscale photocurrent mapping, ultrafast fluorescence and exciton diffusion to observe the detailed morphology of a high-performance blend of PTB7:PC71BM. We show that optimized blends consist of elongated fullerene-rich and polymer-rich fibre-like domains, which are 10–50 nm wide and 200–400 nm long. These elongated domains provide a concentration gradient for directional charge diffusion that helps in the extraction of charge pairs with 80% efficiency. In contrast, blends with agglomerated fullerene domains show a much lower efficiency of charge extraction of ~45%, which is attributed to poor electron and hole transport. Our results show that the formation of narrow and elongated domains is desirable for efficient bulk heterojunction solar cells. The morphology of organic solar cells is crucial to their performance but is difficult to measure. Using a variety of probes, Hedley et al. map the morphology of polymer-fullerene solar cells and find that elongated fibre-like polymer- and fullerene-rich domains are desirable for high performance.
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Choi C, Sborchia C, Ioki K, Giraud B, Utin Y, Sa J, Wang X, Teissier P, Martinez J, Le Barbier R, Jun C, Dani S, Barabash V, Vertongen P, Alekseev A, Jucker P, Bayon A, Pathak H, Raval J, Ahn H, Kim B, Kuzmin E, Savrukhin P. Status of the ITER vacuum vessel construction. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2013.12.056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Tkalya E, Ghislandi M, Otten R, Lotya M, Alekseev A, van der Schoot P, Coleman J, de With G, Koning C. Experimental and theoretical study of the influence of the state of dispersion of graphene on the percolation threshold of conductive graphene/polystyrene nanocomposites. ACS APPLIED MATERIALS & INTERFACES 2014; 6:15113-15121. [PMID: 25116440 DOI: 10.1021/am503238z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The effect of the dispersed state of graphene is studied as a factor influencing the electrical percolation threshold of graphene/polystyrene nanocomposites. We find the percolation threshold of our nanocomposites, prepared with graphene dispersions with different thermodynamic stabilities, degrees of exfoliation, and size polydispersities, to range from 2 to 4.5 wt %. Connectedness percolation theory is applied to calculate percolation thresholds of the corresponding nanocomposites, based on the premise that size polydispersity of graphene platelets in the corresponding solutions must have a strong influence on it. Theory and experimental results agree qualitatively.
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Pashaev B, Bochcarev D, Krasnazhen V, Danilov V, Alekseev A, Vagapova G, Nasibullina F. Prophylaxis and Treatment of CSF Leak in Endonasal Skull Base Surgery. Skull Base Surg 2014. [DOI: 10.1055/s-0034-1383998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Alekseev A, Efimov A, Loos J, Matsko N, Syurik J. Corrigendum to “Three-dimensional imaging of polymer materials by scanning probe tomography” [Eur. Polym. J. 52 (2014) 154–165]. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2014.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sharshov K, Sivay M, Liu D, Pantin-Jackwood M, Marchenko V, Durymanov A, Alekseev A, Damdindorj T, Gao GF, Swayne DE, Shestopalov A. Molecular characterization and phylogenetics of a reassortant H13N8 influenza virus isolated from gulls in Mongolia. Virus Genes 2014; 49:237-49. [DOI: 10.1007/s11262-014-1083-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 05/02/2014] [Indexed: 11/29/2022]
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Alekseev A, Efimov A, Loos J, Matsko N, Syurik J. Three-dimensional imaging of polymer materials by Scanning Probe Tomography. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2014.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Alekseev A, Andreeva Z, Belov A, Belyakov V, Filatov O, Gribov Y, Ioki K, Kukhtin V, Labusov A, Lamzin E, Lyublin B, Malkov A, Mazul I, Rozov V, Sugihara M, Sychevsky S. Efficient approach to simulate EM loads on massive structures in ITER machine. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2013.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rozov V, Alekseev A, Gribov Y, Roccella M, Roccella R, Sannazzaro G, Sugihara M. Output data from simplified electromagnetic models for structure analysis of main ITER components. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2012.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Alekseev A, Arslanova D, Belov A, Belyakov V, Gapionok E, Gornikel I, Gribov Y, Ioki K, Kukhtin V, Lamzin E, Sugihara M, Sychevsky S, Terasawa A, Utin Y. Computational models for electromagnetic transients in ITER vacuum vessel, cryostat and thermal shield. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2013.01.102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rībena D, Alekseev A, van Asselen O, Mannie GJA, Hendrix MMRM, van der Ven LGJ, Sommerdijk NAJM, de With G. Significance of the amide functionality on DOPA-based monolayers on gold. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:16900-16908. [PMID: 23157706 DOI: 10.1021/la303308m] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The adhesive proteins secreted by marine mussels contain an unusual amino acid, 3,4-dihydroxyphenylalanine (DOPA), that is responsible for the cohesive and adhesive strength of this natural glue and gives mussels the ability to attach themselves to rocks, metals, and plastics. Here we report a detailed structural and spectroscopic investigation of the interface between N-stearoyldopamine and a single-crystalline Au(111) model surface and an amide-absent molecule, 4-stearylcatechol, also on Au(111), with the aim of understanding the role of the amide functionality in the packing, orientation, and fundamental interaction between the substrate and the monolayer formed from an aqueous environment by the Langmuir-Blodgett technique. The organization of monolayers on gold was observed directly and studied in detail by X-ray photoelectron spectroscopy (XPS), contact angle measurements (CA), surface-enhanced Raman spectroscopy (SERS), infrared reflection-absorption spectroscopy (IRRAS), and atomic force microscopy (AFM). Our study shows that within the monolayer the catecholic oxygen atoms are coordinated to the gold surface, having a more perpendicular orientation with respect to the aromatic ring and the apparently tilted alkyl chains, whereas the amide functionality stabilizes the monolayer that is formed.
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