220 research outputs found

    Sustainable Technology for Person-Centered Accessible Integrated Multimodal Information Systems

    Get PDF
    This paper reports on a mobility management technology project conducted by the GeoGraphics Laboratory at Bridgewater State University in Bridgewater, Massachusetts, in the Northeastern United States (U.S.). This study is a part of a much larger mobility management technology deployment by the Cape Cod Regional Transit Authority (CCRTA) that deployed integrated intermodal intelligent transportation system (ITS) to support the mobility of a metropolitan region that has a high proportion of elderly residents and persons with disabilities and is a significant tourist destination for national and international travelers. This paper reports on a research project that is developing smartphone applications to provide travelers using transit with navigational tools and real-time spatial information to optimize their travel experience. The smart phone applications are written using the Android 2.2, Windows 7.5, and Apple iOS 4 operating systems. The applications provide the traveler with schedules for every CCRTA regional and shuttle route, estimated time of arrival (ETA), and bus tracking maps (Google and Bing Maps) that locate the transit vehicle and the consumer on the same map as well as text based vehicle tracking. There is an on-line tutorial on how to use the smartphone application. It also provides features that will provide emergency communication with care givers on the consumer’s travel status. The research has developed these transit navigation tools on the three most popular operating systems for smart phones using a widely available cellular carrier. An associated regional capital infrastructure project is bringing state-of-the-art broadband capability and the potential for 4G wireless infrastructure to the most rural “last mile” areas of the Cape Cod Region. These improvements to wireless communications can provide significant benefits to the safety and security of travelers with disabilities

    Bactericidal effect of magnesium ions over planktonic and sessile Staphylococcus epidermidis and Escherichia coli

    Get PDF
    Magnesium and its alloys are in focus to produce implants due to their excellent mechanical properties, facility to decompose in the body, enhancement of new bone formation and antibacterial properties. However, there is still a lack of consensus about the origin of such antibacterial effect. Up to date, most antibacterial studies were performed over newly synthesized MgO particles, nanotubes or nanowires in the form of slurries, integrated within polymeric matrixes or as coatings of other bulk materials whereas the effect of pure Mg2+ions over bacteria viability, in the absence of secondary processes, has not been assessed yet. Hence, in this study, we have characterized the bactericidal effect of Mg2+ions over two different bacteria strains, Staphylococcus epidermidis (Gram-positive) and Escherichia coli (Gram-negative) controlling both pH and ion concentration. Also, we have considered the ion effect on dissimilar planktonic and sessile cells on surfaces with different hydrophobicity

    Structure, morphology, adhesion and in vitro biological evaluation of antibacterial multi-layer HA-Ag/SiO2/TiN/Ti coatings obtained by RF magnetron sputtering for biomedical applications

    Full text link
    [EN] Biocompatible and antibacterial multi-layer coatings of hydroxyapatite (HA)-Ag/SiO2/TiN/Ti were obtained on the Ti-6Al-4V alloy, by means of the magnetron sputtering technique. During characterization of the coatings, the chemical composition was evaluated by energy dispersive X-ray spectroscopy and the phase analysis was carried out by X-ray diffraction. The morphology of the coatings was observed by field emission scanning electron microscopy, while transmission electron microscopy was used to appreciate their structure. The adhesion of the coatings to the substrate was evaluated by micro scratch test. The in vitro biological response was evaluated in terms of cytotoxicity, adhesion and differentiation of mouse mesenchymal stem cells, as well as adhesion and bacterial viability of Staphylococcus aureus strain. Through the compositional study carried out, the deposition of the HA phase was verified, with a Ca/P ratio close to 1.67 and the characteristic diffraction peaks of this compound. The structural study of the coatings evidenced the obtention of multi-layer architectures. The use of an intermediate SiO2/TiN/Ti trilayer was found to improve adhesion between HA-Ag and the substrate by 84%. Finally, the in vitro biological tests carried out indicated a potentially non-toxic character in the coatings. Additionally, an antibacterial effect was registered at low concentrations of Ag (3.0.co;2-3Lalueza, P., Monzón, M., Arruebo, M., & Santamaría, J. (2011). Bactericidal effects of different silver-containing materials. Materials Research Bulletin, 46(11), 2070-2076. doi:10.1016/j.materresbull.2011.06.041Peetsch, A., Greulich, C., Braun, D., Stroetges, C., Rehage, H., Siebers, B., … Epple, M. (2013). Silver-doped calcium phosphate nanoparticles: Synthesis, characterization, and toxic effects toward mammalian and prokaryotic cells. Colloids and Surfaces B: Biointerfaces, 102, 724-729. doi:10.1016/j.colsurfb.2012.09.040Yanovska, A. A., Stanislavov, A. S., Sukhodub, L. B., Kuznetsov, V. N., Illiashenko, V. Y., Danilchenko, S. N., & Sukhodub, L. F. (2014). Silver-doped hydroxyapatite coatings formed on Ti–6Al–4V substrates and their characterization. Materials Science and Engineering: C, 36, 215-220. doi:10.1016/j.msec.2013.12.011DeVasConCellos, P., Bose, S., Beyenal, H., Bandyopadhyay, A., & Zirkle, L. G. (2012). Antimicrobial particulate silver coatings on stainless steel implants for fracture management. Materials Science and Engineering: C, 32(5), 1112-1120. doi:10.1016/j.msec.2012.02.020VALLETREGI, M. (2004). Calcium phosphates as substitution of bone tissues. Progress in Solid State Chemistry, 32(1-2), 1-31. doi:10.1016/j.progsolidstchem.2004.07.001Surmenev, R. A., Surmeneva, M. A., Evdokimov, K. E., Pichugin, V. F., Peitsch, T., & Epple, M. (2011). The influence of the deposition parameters on the properties of an rf-magnetron-deposited nanostructured calcium phosphate coating and a possible growth mechanism. Surface and Coatings Technology, 205(12), 3600-3606. doi:10.1016/j.surfcoat.2010.12.039Surmeneva, M. A., Sharonova, A. A., Chernousova, S., Prymak, O., Loza, K., Tkachev, M. S., … Surmenev, R. A. (2017). Incorporation of silver nanoparticles into magnetron-sputtered calcium phosphate layers on titanium as an antibacterial coating. Colloids and Surfaces B: Biointerfaces, 156, 104-113. doi:10.1016/j.colsurfb.2017.05.016Mohseni, E., Zalnezhad, E., Bushroa, A. R., Abdel Magid Hamouda, Goh, B. T., & Yoon, G. H. (2015). Ti/TiN/HA coating on Ti–6Al–4V for biomedical applications. Ceramics International, 41(10), 14447-14457. doi:10.1016/j.ceramint.2015.07.081Ghasemi, S., Shanaghi, A., & Chu, P. K. (2017). Nano mechanical and wear properties of multi-layer Ti/TiN coatings deposited on Al 7075 by high-vacuum magnetron sputtering. Thin Solid Films, 638, 96-104. doi:10.1016/j.tsf.2017.07.049Hamdi, D. A., Jiang, Z.-T., No, K., Rahman, M. M., Lee, P.-C., Truc, L. N. T., … Dlugogorski, B. Z. (2019). Biocompatibility study of multi-layered hydroxyapatite coatings synthesized on Ti-6Al-4V alloys by RF magnetron sputtering for prosthetic-orthopaedic implant applications. Applied Surface Science, 463, 292-299. doi:10.1016/j.apsusc.2018.08.157Qi, J., Yang, Y., Zhou, M., Chen, Z., & Chen, K. (2019). Effect of transition layer on the performance of hydroxyapatite/titanium nitride coating developed on Ti-6Al-4V alloy by magnetron sputtering. Ceramics International, 45(4), 4863-4869. doi:10.1016/j.ceramint.2018.11.183Lenis, J. A., Hurtado, F. M., Gómez, M. A., & Bolívar, F. J. (2019). Effect of thermal treatment on structure, phase and mechanical properties of hydroxyapatite thin films grown by RF magnetron sputtering. Thin Solid Films, 669, 571-578. doi:10.1016/j.tsf.2018.11.045Lenis, J. A., Gómez, M. A., & Bolívar, F. J. (2019). Effect of deposition temperature and target-substrate distance on the structure, phases, mechanical and tribological properties of multi-layer HA-Ag coatings obtained by RF magnetron sputtering. Surface and Coatings Technology, 378, 124936. doi:10.1016/j.surfcoat.2019.124936Sofronia, A. M., Baies, R., Anghel, E. M., Marinescu, C. A., & Tanasescu, S. (2014). Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite. Materials Science and Engineering: C, 43, 153-163. doi:10.1016/j.msec.2014.07.023Lenis, J. A., Bejarano, G., Rico, P., Ribelles, J. L. G., & Bolívar, F. J. (2019). Development of multilayer Hydroxyapatite - Ag/TiN-Ti coatings deposited by radio frequency magnetron sputtering with potential application in the biomedical field. Surface and Coatings Technology, 377, 124856. doi:10.1016/j.surfcoat.2019.06.097Lenis, J. A., Toro, L. J., & Bolívar, F. J. (2019). Multi-layer bactericidal silver - calcium phosphate coatings obtained by RF magnetron sputtering. Surface and Coatings Technology, 367, 203-211. doi:10.1016/j.surfcoat.2019.03.038Valverde, A., Pérez-Álvarez, L., Ruiz-Rubio, L., Pacha Olivenza, M. A., García Blanco, M. B., Díaz-Fuentes, M., & Vilas-Vilela, J. L. (2019). Antibacterial hyaluronic acid/chitosan multilayers onto smooth and micropatterned titanium surfaces. Carbohydrate Polymers, 207, 824-833. doi:10.1016/j.carbpol.2018.12.039Surmeneva, M. A., Chaikina, M. V., Zaikovskiy, V. I., Pichugin, V. F., Buck, V., Prymak, O., … Surmenev, R. A. (2013). The structure of an RF-magnetron sputter-deposited silicate-containing hydroxyapatite-based coating investigated by high-resolution techniques. Surface and Coatings Technology, 218, 39-46. doi:10.1016/j.surfcoat.2012.12.023Nelea, V., Morosanu, C., Iliescu, M., & Mihailescu, I. N. (2003). Microstructure and mechanical properties of hydroxyapatite thin films grown by RF magnetron sputtering. Surface and Coatings Technology, 173(2-3), 315-322. doi:10.1016/s0257-8972(03)00729-1Ding, S.-J., Ju, C.-P., & Lin, J.-H. C. (1999). Characterization of hydroxyapatite and titanium coatings sputtered on Ti-6Al-4V substrate. Journal of Biomedical Materials Research, 44(3), 266-279. doi:10.1002/(sici)1097-4636(19990305)44:33.0.co;2-4Ivanova, A. A., Surmeneva, M. A., Tyurin, A. I., Pirozhkova, T. S., Shuvarin, I. A., Prymak, O., … Surmenev, R. A. (2016). Fabrication and physico-mechanical properties of thin magnetron sputter deposited silver-containing hydroxyapatite films. Applied Surface Science, 360, 929-935. doi:10.1016/j.apsusc.2015.11.087Contreras Romero, E., Cortínez Osorio, J., Talamantes Soto, R., Hurtado Macías, A., & Gómez Botero, M. (2019). Microstructure, mechanical and tribological performance of nanostructured TiAlTaN-(TiAlN/TaN)n coatings: Understanding the effect of quaternary/multilayer volume fraction. Surface and Coatings Technology, 377, 124875. doi:10.1016/j.surfcoat.2019.07.086Deligianni, D. (2001). Effect of surface roughness of the titanium alloy Ti–6Al–4V on human bone marrow cell response and on protein adsorption. Biomaterials, 22(11), 1241-1251. doi:10.1016/s0142-9612(00)00274-xZareidoost, A., Yousefpour, M., Ghaseme, B., & Amanzadeh, A. (2012). The relationship of surface roughness and cell response of chemical surface modification of titanium. Journal of Materials Science: Materials in Medicine, 23(6), 1479-1488. doi:10.1007/s10856-012-4611-9Surmeneva, M. A., Tyurin, A. I., Mukhametkaliyev, T. M., Pirozhkova, T. S., Shuvarin, I. A., Syrtanov, M. S., & Surmenev, R. A. (2015). Enhancement of the mechanical properties of AZ31 magnesium alloy via nanostructured hydroxyapatite thin films fabricated via radio-frequency magnetron sputtering. Journal of the Mechanical Behavior of Biomedical Materials, 46, 127-136. doi:10.1016/j.jmbbm.2015.02.025Quirama, A., Echavarría, A. M., Meza, J. M., Osorio, J., & Bejarano G, G. (2017). Improvement of the mechanical behavior of the calcium phosphate coatings deposited onto Ti6Al4V alloy using an intermediate TiN/TiO2 bilayer. Vacuum, 146, 22-30. doi:10.1016/j.vacuum.2017.09.024Surmeneva, M. A., Kleinhans, C., Vacun, G., Kluger, P. J., Schönhaar, V., Müller, M., … Surmenev, R. A. (2015). Nano-hydroxyapatite-coated metal-ceramic composite of iron-tricalcium phosphate: Improving the surface wettability, adhesion and proliferation of mesenchymal stem cells in vitro. Colloids and Surfaces B: Biointerfaces, 135, 386-393. doi:10.1016/j.colsurfb.2015.07.057Chen, Y., Zheng, X., Xie, Y., Ji, H., Ding, C., Li, H., & Dai, K. (2010). Silver release from silver-containing hydroxyapatite coatings. Surface and Coatings Technology, 205(7), 1892-1896. doi:10.1016/j.surfcoat.2010.08.073Actis, L., Gaviria, L., Guda, T., & Ong, J. L. (2013). Antimicrobial surfaces for craniofacial implants: state of the art. Journal of the Korean Association of Oral and Maxillofacial Surgeons, 39(2), 43. doi:10.5125/jkaoms.2013.39.2.43Parvizi, J., Aggarwal, V., & Rasouli, M. (2013). Periprosthetic joint infection: Current concept. Indian Journal of Orthopaedics, 47(1), 10. doi:10.4103/0019-5413.106884Redey, S. A., Nardin, M., Bernache-Assolant, D., Rey, C., Delannoy, P., Sedel, L., & Marie, P. J. (2000). Behavior of human osteoblastic cells on stoichiometric hydroxyapatite and type A carbonate apatite: Role of surface energy. Journal of Biomedical Materials Research, 50(3), 353-364. doi:10.1002/(sici)1097-4636(20000605)50:33.0.co;2-cSpriano, S., Bosetti, M., Bronzoni, M., Vernè, E., Maina, G., Bergo, V., & Cannas, M. (2005). Surface properties and cell response of low metal ion release Ti-6Al-7Nb alloy after multi-step chemical and thermal treatments. Biomaterials, 26(11), 1219-1229. doi:10.1016/j.biomaterials.2004.04.026Vogler, E. A. (1999). Water and the acute biological response to surfaces. Journal of Biomaterials Science, Polymer Edition, 10(10), 1015-1045. doi:10.1163/156856299x00667Lim, J. Y., Liu, X., Vogler, E. A., & Donahue, H. J. (2004). Systematic variation in osteoblast adhesion and phenotype with substratum surface characteristics. Journal of Biomedical Materials Research, 68A(3), 504-512. doi:10.1002/jbm.a.20087Sengstock, C., Diendorf, J., Epple, M., Schildhauer, T. A., & Köller, M. (2014). Effect of silver nanoparticles on human mesenchymal stem cell differentiation. Beilstein Journal of Nanotechnology, 5, 2058-2069. doi:10.3762/bjnano.5.214Sahuquillo Arce, J. M., Iranzo Tatay, A., Llácer Luna, M., Sanchis Boix, Y., Guitán Deltell, J., González Barberá, E., … Gobernado Serrano, M. (2011). Estudio in vitro de las propiedades antimicrobianas de una espuma de poliuretano que libera iones de plata. Cirugía Española, 89(8), 532-538. doi:10.1016/j.ciresp.2011.02.015Jamuna-Thevi, K., Bakar, S. A., Ibrahim, S., Shahab, N., & Toff, M. R. M. (2011). Quantification of silver ion release, in vitro cytotoxicity and antibacterial properties of nanostuctured Ag doped TiO2 coatings on stainless steel deposited by RF magnetron sputtering. Vacuum, 86(3), 235-241. doi:10.1016/j.vacuum.2011.06.011Chernousova, S., & Epple, M. (2012). Silver as Antibacterial Agent: Ion, Nanoparticle, and Metal. Angewandte Chemie International Edition, 52(6), 1636-1653. doi:10.1002/anie.20120592

    Ataxia with oculomotor apraxia type 2: clinical, biological and genotype/phenotype correlation study of a cohort of 90 patients

    Get PDF
    Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive disease due to mutations in the senataxin gene, causing progressive cerebellar ataxia with peripheral neuropathy, cerebellar atrophy, occasional oculomotor apraxia and elevated alpha-feto-protein (AFP) serum level. We compiled a series of 67 previously reported and 58 novel ataxic patients who underwent senataxin gene sequencing because of suspected AOA2. An AOA2 diagnosis was established for 90 patients, originating from 15 countries worldwide, and 25 new senataxin gene mutations were found. In patients with AOA2, median AFP serum level was 31.0 mu g/l at diagnosis, which was higher than the median AFP level of AOA2 negative patients: 13.8 mu g/l, P = 0.0004; itself higher than the normal level (3.4 mu g/l, range from 0.5 to 17.2 mu g/l) because elevated AFP was one of the possible selection criteria. Polyneuropathy was found in 97.5% of AOA2 patients, cerebellar atrophy in 96%, occasional oculomotor apraxia in 51%, pyramidal signs in 20.5%, head tremor in 14%, dystonia in 13.5%, strabismus in 12.3% and chorea in 9.5%. No patient was lacking both peripheral neuropathy and cerebellar atrophy. The age at onset and presence of occasional oculomotor apraxia were negatively correlated to the progression rate of the disease (P = 0.03 and P = 0.009, respectively), whereas strabismus was positively correlated to the progression rate (P = 0.03). An increased AFP level as well as cerebellar atrophy seem to be stable in the course of the disease and to occur mostly at or before the onset of the disease. One of the two patients with a normal AFP level at diagnosis had high AFP levels 4 years later, while the other had borderline levels. The probability of missing AOA2 diagnosis, in case of sequencing senataxin gene only in non-Friedreich ataxia non-ataxia-telangiectasia ataxic patients with AFP level >= 7 mu g/l, is 0.23% and the probability for a non-Friedreich ataxia non-ataxia-telangiectasia ataxic patient to be affected with AOA2 with AFP levels >= 7 mu g/l is 46%. Therefore, selection of patients with an AFP level above 7 mu g/l for senataxin gene sequencing is a good strategy for AOA2 diagnosis. Pyramidal signs and dystonia were more frequent and disease was less severe with missense mutations in the helicase domain of senataxin gene than with missense mutations out of helicase domain and deletion and nonsense mutations (P = 0.001, P = 0.008 and P = 0.01, respectively). The lack of pyramidal signs in most patients may be explained by masking due to severe motor neuropathy

    Decreased Serologic Response in Vaccinated Military Recruits during 2011 Correspond to Genetic Drift in Concurrent Circulating Pandemic A/H1N1 Viruses

    Get PDF
    Population-based febrile respiratory illness surveillance conducted by the Department of Defense contributes to an estimate of vaccine effectiveness. Between January and March 2011, 64 cases of 2009 A/H1N1 (pH1N1), including one fatality, were confirmed in immunized recruits at Fort Jackson, South Carolina, suggesting insufficient efficacy for the pH1N1 component of the live attenuated influenza vaccine (LAIV).To test serologic protection, serum samples were collected at least 30 days post-vaccination from recruits at Fort Jackson (LAIV), Parris Island (LAIV and trivalent inactivated vaccine [TIV]) at Cape May, New Jersey (TIV) and responses measured against pre-vaccination sera. A subset of 78 LAIV and 64 TIV sera pairs from recruits who reported neither influenza vaccination in the prior year nor fever during training were tested by microneutralization (MN) and hemagglutination inhibition (HI) assays. MN results demonstrated that seroconversion in paired sera was greater in those who received TIV versus LAIV (74% and 37%). Additionally, the fold change associated with TIV vaccination was significantly different between circulating (2011) versus the vaccine strain (2009) of pH1N1 viruses (ANOVA p value = 0.0006). HI analyses revealed similar trends. Surface plasmon resonance (SPR) analysis revealed that the quantity, IgG/IgM ratios, and affinity of anti-HA antibodies were significantly greater in TIV vaccinees. Finally, sequence analysis of the HA1 gene in concurrent circulating 2011 pH1N1 isolates from Fort Jackson exhibited modest amino acid divergence from the vaccine strain.Among military recruits in 2011, serum antibody response differed by vaccine type (LAIV vs. TIV) and pH1N1 virus year (2009 vs. 2011). We hypothesize that antigen drift in circulating pH1N1 viruses contributed to reduce vaccine effectiveness at Fort Jackson. Our findings have wider implications regarding vaccine protection from circulating pH1N1 viruses in 2011-2012

    <i>Chlamydia trachomatis</i>: prevalencia en muestras cervicovaginalis

    Get PDF
    El objetivo del trabajo es establecer la prevalencia de C. trachomatis en muestras de endocervix de mujeres sexualmente activas que concurren a la consulta ginecológica ambulatoria ,por patología de enfermedades de transmisión sexual y por causas de infertilidad.Facultad de Ciencias Veterinaria

    Investigación de prevalencia y sensibilidad antibiótica de <i>Ureaplasma urealyticum</i> en infecciones genitales femeninas

    Get PDF
    Ureaplama urealyticum pertenece a la Clase de los Mollicutes (de cutis mollis:piel blanda). Se diferencian de otras bacterias entre otras cosas por la ausencia de pared celular, que les confiere una resistencia natural a los betas lactámicos, así también como la presencia de una membrana con esteroles provenientes de las membaranas de las células eucariotas sobre las que se fijan. No se multiplican en medios acelulares, por lo cual requiere medios especiales para su desarrollo como agar PPLO suplementado con suero equino, extracto de levadura y urea. Desde hace varios años se ha vinculado la asociación de U. urealyticum con una serie de patologías femeninas tales como salpingitis, infecciones intrauterinas, fiebre post parto y post aborto, problemas de infertilidad y bajo peso de los neonatos, así como también pielonefritis, cálculos urinarios entre otras. El objetivo del trabajo es establecer la prevalencia y sensibilidad antibiótica de U. urealyticum genitales en las muestras provenientes de pacientes mujeres que concurren a la consulta ginecológica ambulatoria.Facultad de Ciencias Veterinaria

    Investigación de prevalencia y sensibilidad antibiótica de Ureaplasma urealyticum en infecciones genitales femeninas

    Get PDF
    Ureaplama urealyticum pertenece a la Clase de los Mollicutes(de cutis mollis: piel blanda). Se diferencian de otras bacterias entre otras cosas por la ausencia de pared celular, que les confiere una resistencia natural a los betas lactámicos, así también como la presencia de una membrana con esteroles provenientes de las membaranas de las células eucariotas sobre las que se fijan. No se multiplican en medios acelulares, por lo cual requiere medios especiales para su desarrollo como agar PPLO suplementado con suero equino, extracto de levadura y urea. Desde hace varios años se ha vinculado la asociación de U. urealyticum con una serie de patologías femeninas tales como salpingitis, infecciones intrauterinas, fiebre post parto y post aborto, problemas de infertilidad y bajo peso de los neonatos, así como también pielonefritis, cálculos urinarios entre otras. El objetivo del trabajo es establecer la prevalencia y sensibilidad antibiótica de U. urealyticum genitales en las muestras provenientes de pacientes mujeres que concurren a la consulta ginecológica ambulatoria.Facultad de Ciencias Veterinaria

    Chlamydia trachomatis: prevalencia en muestras cervicovaginalis

    Get PDF
    El objetivo del trabajo es establecer la prevalencia de C. trachomatis en muestras de endocervix de mujeres sexualmente activas que concurren a la consulta ginecológica ambulatoria ,por patología de enfermedades de transmisión sexual y por causas de infertilidad.Facultad de Ciencias Veterinaria
    corecore