Electrochemical characterization of a novel salen type modified electrode

The nickel(II) complex with H2saltMe, a N2O2 Schiff base ligand derived from salicylaldehyde, was oxidatively electropolymerized on Pt electrodes in CH3CN/0.1 mol dm-3 tetraethylammonium perchlorate (TEAP) to generate polymer films that exhibit reversible oxidative electrochemical behavior in a wide potential range (0.0-1.3 V), high conductivity, and stability/durability

A combined electrochemical quartz-crystal microbalance probe beam deflection (EQCM-PBD) study of solvent and ion transfers at a poly[Ni(saltMe)]: modified elecrode during redox switching

The oxidative polymerization of the complex2,3-dimelhyl-N,N-bis( salicylidene)butane-2,3-diaminatonickel( n), [Ni(saltMe)], was monitored by the electrochemical quartz microbalance (EQCM) and crystal impedance techniques. Polymerisation efficiency was maintained throughout deposition of a film, which behaved rigidly, on the electrode

Oxidation of ferrocene derivatives at a Poly[Ni(saltMe)] modified electrode

The characterization of film permeability and mediation properties of poly[Ni(saltMe)] modified electrodes were evaluated by studying the oxidation of ferrocene and 1,1’-dimethylferrocene at these electrodes by rotating-disk voltammetry. The effects of varying the substrate and its solution concentration, film thickness, rotation speed and electrode potential on the limiting current density were analysed using the model of Albery

Spectroelectrochemical characterisation of a poly[Ni(saltMe)] modified electrode

Electrogenerated polymers based on the nickel(II) compIex 2,3-dimetbyl- N,N -bis(salicylidene )butane-2,3- diaminatoniekel(II), poly[Ni(saltMe)], were characterized by in situ FTIR and UV/Vis spectroscopy and ex-situ EPR spectroscopy in order to gain insights into film structure, electronic states and charge conduction. The role of the nickel ions during film oxidation was probed by using EPR to study naturally abundant Ni and 61Ni-enriehed polymers

Electrochemical behavior of a new precursor for the design of poly[Ni(salen)]-based modified electrodes

Wedescribe the potentiodynamic preparation and subsequent characterization of poly[Ni(3-MeOsaltMe)] films (surface concentration, 3 < ¡/nmol cm-2 < 350) in acetonitrile media. Coulometric and gravimetric (electrochemical quartz crystal microbalance, EQCM) data allow one to monitor the deposition process and show that the resultant films are physically and chemically stable

Spectroelectrochemical characterisation of copper salen-based polymer modified electrode

Electrogenerated polymers based on copper salen-type complexes were characterised electrochemically and by in situ UV–vis and ex situ EPR spectroscopy. The films, poly[Cu(salen)] and poly[Cu(saltMe)], exhibit reversible oxidative electrochemical behaviour in a wide potential range (0.0–1.5 V). Different regimes for charge transport behaviour are accessed by manipulation of film thickness and experimental time scale: thin films (surface concentration, Γ ca. 90 nmol cm−2) exhibit a changeover from thin-layer to diffusion control regime at a critical scan rate that depends on polymer and film thickness: 0.15–0.20 V s−1 for poly[Cu(salen)], 90 < Γ < 130 nmol cm−2 and 0.20–0.30 V s−1 for poly[Cu(saltMe)], 170 < Γ < 230 nmol cm−2. UV–vis and EPR spectroscopies have allowed the characterisation of electronic states in the reduced and oxidised forms. The role of the copper atom during film oxidation was probed by combining UV–vis data with EPR on copolymers of the copper and nickel complexes. Data from both techniques are consistent and indicate that polymerisation and redox switching are associated with ligand-based processes. EPR of Ni-doped Cu polymers provided evidence for the non-involvement of the metal centre in polymer oxidation; like the analogous nickel polymers, copper polymers behave like delocalised π-system (‘conducting’) rather than discrete site (‘redox’) polymers

Natural and human-induced coastal dynamics at a back-barrier beach

This study contributes to the understanding of very low-energy fetch-limited environments by reporting the evolution of a back-barrier beach (Ancão Peninsula, southern Portugal). It considers two timescales: a large-scale evolution for the past 60 years based on aerial photograph analysis, and a small-scale beach evolution based on monthly topographic surveys performed during three years of monitoring. Each timescale revealed a different rate of evolution, the first reporting a modified beach response-type (from human activities), and the second reporting a natural beach response-type. Human activities caused significant changes in the back-barrier shore, whereas changes under natural forcing were much smaller, were less influential on the area's evolution, and were not sufficient to counteract or mask the consequences of human activities. The findings of the study should contribute to a better understanding about the large- and small- scale changes in other back-barriers characterised by similar very low-energy conditions.info:eu-repo/semantics/publishedVersio

Biomecánica del pilar canino en el cráneo humano basada en la geometría utilizando análisis de elementos finitos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)This study evaluated the stress distribution based on the canine pillar geometry in human skull, using a finite element analysis. Computed tomography of human skull was used to build a finite element model, which was composed by all bony structures of canine pillar: canine eminence, canine fossa, frontal process of maxilla, glabellum and superciliary arch. A support on the bite contact of maxillary canine tooth and a resultant force of the masticatory muscles was applied in the simulation. Equivalent Von-mises and maximum principal stresses were analyzed along the structures that compose the canine pillar geometry. Von-mises stress presented high stress concentrated at the canine fossa and frontal process of maxilla. Maximum principal stress showed compression areas at the canine fossa and part of frontal process and tensile stress at canine eminence and part of the frontal process. In conclusion, the different stress areas means different force concentrations transmitted along the canine pillar geometry during a peak canine bite.This study evaluated the stress distribution based on the canine pillar geometry in human skull, using a finite element analysis. Computed tomography of human skull was used to build a finite element model, which was composed by all bony structures of can321214220CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)sem informaçãoEste estudio evaluó la distribución de la tensión sobre la geometría del pilar canino en el cráneo humano, utilizando análisis de elementos finitos. Se usó la tomografía computarizada de cráneo humano para construir un modelo de elementos finitos compuestBrazil for financial support and the Center for Information Technology “Renato Archer” (Campinas, Brazil) for technical and scientific suppor

Incidence Of The Ossified Pterygoalar Ligament In Brazilian Human Skulls And Its Clinical Implications

The ossified pterygoalar ligament is formed between the lateral lamina of the pterygoid process and the infratemporal surface of the sphenoid bone or its greater wing and was not connected to the sphenoid spine. The aim of this study was to evaluate the incidence of the ossified pterygoalar ligament in Brazilian human skulls and analyzing its clinical importance. 183 Brazilian adult (between 30 to 60 years old) dry human skulls were evaluated. Was evaluated the incidence of skulls with complete or partial ossification of the pterygoalar ligament, bilaterally and unilaterally and in the presence on the right and left sides. Were found 5 skulls had the ossified pterygoalar ligament, resulting in an overall incidence of 2.73%. There was 1 skull in the presence of the incomplete ossification of the pterygoalar ligament, unilaterally and on the left side resulting in incidence of 0.54%. There were 4 skulls in the presence of the complete ossification of the pterygoalar ligament, unilaterally and on the right side resulting in incidence of 2.18%. The ossified pterygoalar ligament is a major cause of the entrapment of the lingual nerve or a branch of the mandibular nerve and may cause mandibular neuralgia. The incidence of the ossified pterygoalar ligament and the pterygoalar foramen is low in the Brazilian population. However, these structures have clinical significance as this ligament establish relationships with the ovale foramen and difficulty in accessing in this foramen in a therapeutic approach.2816971Antonopoulou, M., Piagou, M., Anagnostopoulou, S., An anatomical study of the pterygospinous and pterygoalar bars and foramina - their clinical relevance (2008) Journal of Cranio-Maxillofacial Surgery, 36 (2), pp. 104-108Das, S., Paul, S., Ossified pterygospinous ligament and its clinical implications (2007) Bratislavské Lekárske Listy, 108 (3), pp. 141-143Erdogmus, S., Pinar, Y., Celik, S., A cause of entrapment of the lingual nerve: Ossified pterygospinous ligament - A case report (2009) Neuroanatomy, 8, pp. 43-45Kapur, E., Dilberović, F., Redzepagić, S., Berhamović, E., Variation in the lateral plate of the pterygoid process and the lateral subzygomatic approach to the mandibular nerve (2000) Medicinski Arhiv, 54 (3), pp. 133-137Krmpotic-Nemanic, J., Vinter, I., Hat, J., Jalsovec, D., Mandibular neuralgia due to anatomical variations (1999) European Archives of Oto-Rhino-Laryngology, 256 (4), pp. 205-208. , DOI 10.1007/s004050050141Ludinghausen, M., Kageyama, I., Miura, M., Alkhatib, M., Morphological peculiarities of the deep infratemporal fossa in advanced age (2006) Surgical and Radiologic Anatomy, 28, pp. 284e-292eNayak, S.R., Saralaya, V., Prabhu, L.V., Pai, M.M., Vadgaonkar, R., D'Costa, S., Pterygospinous bar and foramina in Indian skulls: Incidence and phylogenetic significance (2007) Surgical and Radiologic Anatomy, 29 (1), pp. 5-7. , DOI 10.1007/s00276-006-0154-4Patnaik, W.G., Rajan Singla, K., Bala, S., Bilateral pterygo-alar bar and porus crotaphitico-buccinatorius e a case report (2001) Journal of the Anatomical Society of India, 50, pp. 161-162Peker, T., Karakose, M., Anil, A., Turgut, H.B., Gulekon, N., The Incidence of Basal Sphenoid Bony Bridges in Dried Crania and Cadavers: Their Anthropological and Clinical Relevance (2002) European Journal of Morphology, 40 (3), pp. 171-180. , DOI 10.1076/ejom.40.3.171.16686Peuker, E.T., Fischer, G., Filler, T.J., Entrapment of the lingual nerve due to an ossified pterygospinous ligament (2001) Clinical Anatomy, 14 (4), pp. 282-284. , DOI 10.1002/ca.1048Piagkou, M.N., Demesticha, T., Piagkos, G., Androutsos, G., Skandalakis, P., Mandibular nerve entrapment in the infratemporal fossa (2010) Surgical and Radiologic Anatomy, 10Shaw, J.P., Pterydospinous and pterygoalar foramina: A role in the etiology of trigeminal neuralgia? (1993) Clinical Anatomy, 6, pp. 173e-178eSkrzat, J., Walocha, J., Srodek, R., An anatomical study of the pterygoalar bar and the pterygoalar foramen (2005) Folia Morphologica, 64 (2), pp. 92-96Suazo Galdames, I., Zavando Matamala, D., Smith, R.L., Anatomical study of the pterygospinous and pterygoalar bony bridges and foramens in dried crania and its clinical relevance (2010) International Journal of Morphology, 28 (2), pp. 405-408Williams, P.L., Bannister, L.H., Berry, M.M., Collin, P., Dyson, M., Dussek, J.E., Ferguson, M.W.J., (2000) Gray's Anatomy, pp. 588-801. , 38th ed. New York: Churchill Livingston