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51. Donor Surgical Morbidity in Pediatric Living-Donor Liver Transplant: A Portuguese Experience.

Author

Fernandes dos Santos, José Pedro, Martins, Ricardo, and Lopes, Maria Francelina

Subjects
*LIVER transplantation, *SURGICAL complications, *TRANSPLANTATION of organs, tissues, etc., *BILIARY tract, *CHILDREN'S hospitals, *CHARITABLE giving, *GALLBLADDER cancer, *KIDNEY failure
Abstract

Purpose: Living-donor liver transplant emerged as an alternative treatment for end stage liver disease due to the lack of cadaveric organs availability that met the demand. In Portugal, pediatric living-donor liver transplant (P-LDLT) was initiated in 2001 in Portugal in order to compensate for the scarcity of cadaveric organs for such cases. The aim of this study was to retrospectively analyze the morbi-mortality of the 28 donors included in P-LDLT program performed at Coimbra's Pediatric Hospital (CHUC), a Portuguese reference center. Methods: We retrospectively collected pertinent donor data and stratified complications according to Clavien's scoring system. Results: In total, 28.6% (n=8) of the donors had surgical complications. According to Clavien-Dindo's classification, two donors had major complications (Clavien grade ≥3), four donors had grade 2 complications, and two donors had grade 1 complications. There were no P-LDLT-related mortalities in the present case series. The most common verified complications were biliary tract injuries and superficial incisional infections, which are consistent with the complications reported in worldwide series. Conclusion: These patients from CHUC shows that donor hepatectomy in P-LDLT is a safe procedure, with low morbidity and without mortality. [ABSTRACT FROM AUTHOR]

Published
2021
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52. Projeto mecânico de um tribómetro bloco - disco

Author

Santos, José Pedro Gonçalves dos and Pinto, Arnaldo Manuel Guedes

Subjects
Projeto, Tribologia, Tribology, Tribómetro, Friction, Wear, Atrito, Block-on-ring, Project, Desgaste, Bloco-disco, Tribometer
Abstract

Submitted by Ana Rebelo (amsr@isep.ipp.pt) on 2020-03-23T09:51:54Z No. of bitstreams: 1 DM_JosePedroSantos_2019_MEM.pdf: 16012714 bytes, checksum: 4f99b6c4ea0ef438bfa28ea87b56e43a (MD5) Approved for entry into archive by Ana Rebelo (amsr@isep.ipp.pt) on 2020-03-23T09:52:41Z (GMT) No. of bitstreams: 1 DM_JosePedroSantos_2019_MEM.pdf: 16012714 bytes, checksum: 4f99b6c4ea0ef438bfa28ea87b56e43a (MD5) Made available in DSpace on 2020-03-23T09:52:42Z (GMT). No. of bitstreams: 1 DM_JosePedroSantos_2019_MEM.pdf: 16012714 bytes, checksum: 4f99b6c4ea0ef438bfa28ea87b56e43a (MD5) Previous issue date: 2019

Published
2019

56. Development of Tin Oxide-Based Nanosensors for Electronic Nose Environmental Applications

Author

Consejo Superior de Investigaciones Científicas (España), Sayago, Isabel, Aleixandre, Manuel, Santos, José Pedro, Consejo Superior de Investigaciones Científicas (España), Sayago, Isabel, Aleixandre, Manuel, and Santos, José Pedro

Abstract

Tin oxide nanofibres (NFs) are used as nanosensors in electronic noses. Their performance is compared to that of oxide commercial chemical sensors for pollutant detection. NFs were grown by electrospinning and deposited onto silicon substrates with integrated micro-hotplates. NF morphology was characterized by scanning electron microscopy (SEM). The NFs presented high sensitivity to NO2 at low temperature.

Published
2019

57. Use of Electronic Noses for Diagnosis of Digestive and Respiratory Diseases through the Breath

Author

Consejo Superior de Investigaciones Científicas (España), Comunidad de Madrid, Sánchez, Carlos, Santos, José Pedro, Lozano, Jesús, Consejo Superior de Investigaciones Científicas (España), Comunidad de Madrid, Sánchez, Carlos, Santos, José Pedro, and Lozano, Jesús

Abstract

The increased occurrence of chronic diseases related to lifestyle or environmental conditions may have a detrimental effect on long-term health if not diagnosed and controlled in time. For this reason, it is important to develop new noninvasive early diagnosis equipment that allows improvement of the current diagnostic methods. This, in turn, has led to an exponential development of technology applied to the medical sector, such as the electronic nose. In addition, the appearance of this type of technology has allowed the possibility of studying diseases from another point of view, such as through breath analysis. This paper presents a bibliographic review of past and recent studies, selecting those investigations in which a patient population was studied with electronic nose technology, in order to identify potential applications of this technology in the detection of respiratory and digestive diseases through the analysis of volatile organic compounds present in the breath.

Published
2019

58. Prótese total inferior mucosuportada vs. prótese total inferior implanto mucosuportada

Author

Santos, José Pedro de Carvalho Madureira Torres dos and Maurício, Paulo

Subjects
Terapêutica, Prótese total inferior implanto mucosuportada, Prótese total inferior mucosuportada, Edentulismo
Abstract

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz Com o aumento da esperança média de vida, as consequências do edentulismo fazem-se sentir cada vez mais em todas as comunidades. São afetadas as funções mastigatória, fonética e deglutição, a estética e a harmonia facial. Para a reabilitação de uma mandíbula totalmente edêntula, existem várias opções de tratamento. A opção de uma prótese total inferior mucosuportada tem como vantagens o baixo custo e a relativa rapidez dos procedimentos clínicos e laboratoriais. Por outro lado, a reabilitação com uma prótese total inferior implanto mucosuportada tem como vantagens a melhoria das propriedades biomecânicas (retenção, estabilidade e suporte), da qualidade de vida e, consequentemente, da satisfação dos pacientes. A escolha da opção de tratamento é determinada por diversos fatores, tais como o custo, a existência de indicações e/ou contra-indicações à reabilitação com recurso a implantes e as condições intra-orais do paciente a reabilitar. No entanto, a reabilitação de uma mandíbula edêntula com uma prótese total implanto mucosuportada sobre dois implantes constitui a alternativa terapêutica com uma melhor relação custo/benefício. Estabelecido no Consenso de McGill, estas próteses associadas a dois implantes constituem, atualmente, o tratamento standard do edentulismo mandibular.

Published
2017

61. Odoramanita: discriminación de setas con sistemas olfativos artificiales

Author

Portalo-Calero, Francisco, Santos, José Pedro, Sánchez, Carlos, Arroyo, Patricia, Lozano, Jesús, Portalo-Calero, Francisco, Santos, José Pedro, Sánchez, Carlos, Arroyo, Patricia, and Lozano, Jesús

Abstract

[Resumen] Se describen en esta comunicación los primeros pasos para implementar dispositivos inteligentes capaces de discriminar especies de setas utilizando sistemas olfativos artificiales, también conocidos como narices electrónicas. Se orientan las investigaciones a desarrollos accesibles, de bajo coste, portables y con autonomía suficiente en consumo y conectividad, para utilizar tanto en prácticas profesionales como por parte de aficionados a la micología. Se comienza estableciendo una serie de protocolos de recogida, manipulación, y conservación de individuos, centrados en las especies del género Amanita presentes en el suroeste de la península ibérica, y especialmente en aquellas singularmente significativas por su comestibilidad, y principalmente por su toxicidad. Los resultados obtenidos han sido, aunque no definitivos, alentadores para continuar trabajando en esta línea de investigación, que puede aportar soluciones de carácter industrial en procesos de clasificación, conservación y obtención de aromas de setas, así como en el diseño de dispositivos más orientados a la educación medioambiental y el ecoturismo., [Abstract] The first steps to implement devices capable of discriminating species of mushrooms using an electronic nose are described in this communication.The research is oriented to accessible, low cost, portable and with sufficient autonomy, in consumption and connectivity to use both professional practices, as well as amateur mycology.It begins by establishing a series of protocols for collection, handling, and conservation of individuals, focusing on the species of the genus Amanita present in the southwest of the Iberian Peninsula, and especially in that singularly important for its edibility and primarily for its toxicity. The results obtained have been, although not definitive, encouraging to continue working in this line of research, which can provide industrial benefits in processes of classification, conservation and transport of mushrooms, as well as in devices more oriented to environmental education and ecotourism

Published
2018

62. O emprego da Artilharia em operações contra Ameaças Híbridas

Author

Santos , José Pedro Duarte dos and Rego, Nelson José Mendes

Subjects
Guerra Híbrida, Artilharia de Campanha, Ameaça Híbrida, Capacidades, Ciências Sociais::Outras Ciências Sociais [Domínio/Área Científica]
Abstract

O presente trabalho tem como objeto de estudo as capacidades da Artilharia de Campanha, em particular, as que permitem o combate às ameaças híbridas. O objetivo do estudo é descrever as capacidades das ameaças híbridas, assim como as capacidades da Artilharia de Campanha e determinar se a mesma se releva eficaz como apoio de fogos no combate a ameaças híbridas. Para responder a esta questão, adotou-se uma abordagem metodológica indutiva baseada na recolha e análise de dados e documentos. Através deste estudo, é possível concluir que, ao nível da doutrina e da organização, a Artilharia de Campanha possui capacidades que lhe permitem empenhar-se com eficácia contra ameaças híbridas. No entanto, é necessário desenvolver ou adotar munições que permitam bater eficazmente alvos móveis com elevada proteção. In this essay we discuss the Field Artillery’s capabilities, specially the ones that could be used to fight hybrid threats. The goal is to describe the capabilities of the hybrid threat, as well as the capabilities of the Field Artillery and determine if it proves to be an effective fire support element in the combat against hybrid threats. To reach these goals, an inductive method approach based on document analysis was used. In conclusion, this study illustrates that Field Artillery has capabilities that enable it to effectively engage hybrid threats in what concerns to doctrine and organization. Nonetheless, it is necessary to develop or adopt ammunition to effectively engage moving targets with high protection.

Published
2017

63. Electronic Noses Applications in Beer Technology

Author

Santos, José Pedro

Subjects
Technology & Engineering / Industrial Design
Abstract

This chapter describes and explains in detail the electronic noses (e-noses) as devices composed of an array of sensors that measure chemical volatile compounds and apply classification or regression algorithms. Then, it reviews the most significant applications of such devices in beer technology, with examples about defect detection, hop classification, or beer classification, among others. After the review, the chapter illustrates two applications from the authors, one about beer classification and another about beer defect detection. Finally, after a comparison with other analytical techniques, the chapter ends with a summary, conclusions, and the compelling future of the e-noses applied to beer technology.

Published
2017

64. List of contributors

Author

Agrawal, Abhay V., Aleixandre, Manuel, Abdeltif, Amrane, Amutheesan, M., Aslam, Muhammad, Assadi, Aymen Amine, Baysal, Asli, Bharathi, Velayutha Pandian, Bouzaza, Abdelkrim, Campos-Montiel, Rafael G., Dai, Chaomeng, Elancheran, R., Estrada, José M., Fernández-Luqueño, Fabián, García-Mayagoitia, Selvia, Govindhan, R., Gundhavi devi, M., Habib, Nitasha, Hosseinabadi, Majid Bagheri, Jaciw-Zurakowsky, Ivana, Jeno, Jose Gnanaleela Aswin, Juan, Joon Ching, Karthikeyan, Balakrishnan, Khan, Asim Laeeq, Khan, Atif, Kumar, Mukesh, Lai, Chin Wei, Lee, Kian Mun, Leong, Kah Hon, Liang, Robert L., Loganathan, Sivachandiran, Medina-Pérez, Gabriela, Moradi, Mahmood, Nakkeeran, Ekambaram, Ng, Jit Jang, Nguyen, Thien Vuong, Nguyen, Tuan Anh, Nguyen-Tri, Phuong, Oh, Wen-Da, Pérez-Hernández, Hermes, Quijano, Guillermo, Rao, T. Subba, Rathna, Ravichandran, Rtimi, Sami, Santos, Jose Pedro, Saoud, Wala Abou, Saravanan, Pichiah, Sayago, Isabel, Saygin, Hasan, Schneider, Olivia M., Sim, Lan Ching, Sivagami, Nedumaran, Snowdon, Monika R., Sushma, Tai, Xin Hong, Ujihara, Masaki, Wolbert, Dominique, Yadav, Anoop, Yousefi, Ramin, and Zhou, Y. Norman

Published
2020
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65. Desenvolvimento do protótipo do produto'VIIV'

Author

Santos , José Pedro Araújo Silva and Lima, Luis Miguel Vieira

Subjects
Cartão SD, SD card, Bluetooth, LPCOpen, Embedded systems, Sistemas Autónomos, Controladores de ambiente para terrários, Sistemas embebidos, Terrarium controllers, TFT táctil, ARM microcontroller, Touchscreen TFT, emWin, Microcontrolador ARM
Abstract

Submitted by Ana Rebelo (amsr@isep.ipp.pt) on 2017-06-22T11:31:01Z No. of bitstreams: 1 DM_JoseSantos_2016_MEEC.pdf: 7140664 bytes, checksum: 8866b7cca94937f8d2f0ce6f33b9dca6 (MD5) Approved for entry into archive by Ana Rebelo (amsr@isep.ipp.pt) on 2017-06-22T11:31:30Z (GMT) No. of bitstreams: 1 DM_JoseSantos_2016_MEEC.pdf: 7140664 bytes, checksum: 8866b7cca94937f8d2f0ce6f33b9dca6 (MD5) Made available in DSpace on 2017-06-22T11:31:30Z (GMT). No. of bitstreams: 1 DM_JoseSantos_2016_MEEC.pdf: 7140664 bytes, checksum: 8866b7cca94937f8d2f0ce6f33b9dca6 (MD5) Previous issue date: 2016

Published
2016

67. Tin Dioxide-Graphene Based Chemi-Device for NO2 Detection in the Sub ppm Range

Author

Ministerio de Economía y Competitividad (España), Consejo Superior de Investigaciones Científicas (España), Santos, José Pedro, Polichetti, Tiziana, Aleixandre, Manuel, Hontañón, Esther, Sayago, Isabel, Alfano, Brigida, Miglietta, Maria Lucia, Francia, Girolamo Di, Ministerio de Economía y Competitividad (España), Consejo Superior de Investigaciones Científicas (España), Santos, José Pedro, Polichetti, Tiziana, Aleixandre, Manuel, Hontañón, Esther, Sayago, Isabel, Alfano, Brigida, Miglietta, Maria Lucia, and Francia, Girolamo Di

Abstract

Chemical nanodevices based on tin dioxide, graphene and a mixture of both materials were developed and characterized for NO2 detection at low concentrations. The chemiresistors were prepared by both electrospinning and drop casting. The films morphologies were investigated by scanning electron microscopy (SEM). The devices response to sub-ppm NO2 concentrations was measured from room temperature up to 300 °C. An improvement in the performance in terms of sensitivity and response time, as well as higher responses at room temperature, was obtained when a mixture of these materials is used.

Published
2017

69. Identificación de diferentes zumos mediante nariz electrónica portátil

Author

González, Sara, Palomeque-Mangut, David, Fernández Muñoz, Juan Álvaro, Santos, José Pedro, Lozano, Jesús, González, Sara, Palomeque-Mangut, David, Fernández Muñoz, Juan Álvaro, Santos, José Pedro, and Lozano, Jesús

Abstract

[Resumen] Se describe en esta comunicación una nariz electrónica portátil con conexión wifi para la identificación de aromas. La nariz electrónica es fácil de utilizar y es autónoma gracias a sus baterías. Consta de un sistema de una bomba para la extracción de los aromas, microsensores resistivos y un microcontrolador para el control de todo el sistema. Además tiene conexión a internet y una pantalla táctil a color. Por último, mediante un sistema de reconocimiento de patrones se procesan los datos obtenidos de los sensores para conseguir una clasificación de las muestras en categorías previamente aprendidas. Los resultados muestran que el sistema permita la clasificación de cuatro sabores de zumos diferentes.

Published
2016

71. SELFNET Framework self-healing capabilities for 5G mobile networks

Author

Santos, José Pedro, primary, Alheiro, Rui, additional, Andrade, Luís, additional, Valdivieso Caraguay, Ángel Leonardo, additional, Barona López, Lorena Isabel, additional, Sotelo Monge, Marco Antonio, additional, Garcia Villalba, Luís Javier, additional, Jiang, Wei, additional, Schotten, Hans, additional, Alcaraz-Calero, Jose M., additional, Wang, Qi, additional, and Barros, Maria João, additional

Published
2016
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72. Love-wave sensors based in graphene oxide for the detection of chemical warfare agent simulants

Author

Sayago, I., Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, M. C., Muñoz, Edgar, and Ministerio de Economía y Competitividad (España)

Subjects
Chemical warfare agent simulants, Love-wave, Acoustic wave gas sensor, Graphene oxide
Abstract

2 figures.-- Poster presented at the 7as Jornadas Hispano‐Francesas, Meeting IBERNAM-CMC2. Microsystems & Nanotechnology. November 20th-21st, 2014, Naturgas Energía, Bilbao, Spain., Graphene oxide (GO) is a very attractive nanomaterial for sensor applications as it combines 2D structural features of graphene and the presence of oxygen-containing functional groups (mainly, epoxide, hydroxyl and carbonyl groups) (1,2) which can potentially interact with a great variety of analytes. Besides, GO offers promise for its use as substrate to be interfaced with biomolecules and cells for biological detection. Recent studies have focused on the applications of the GO in resistive sensors for the detection of pollutant gases (such as CO2, NH3, H2, NO), chemical warfare agent (CWAs) and explosives (3,4). However, to the best of our knowledge, GO has hardly been used in SAW or Love-wave sensors (5). We have developed a Love-wave SAW sensor with three-layer structure consists in ST-cut quartz as substrate, SiO2 as guiding layer and GO as sensitive layer. In this work, we present the first results obtained with GO Love-SAW sensor for the detection of CWA simulants. The sensor detected very low concentrations of dimethyl-methylphosphonate (DMMP) and dipropylene glycol monomethyl ether (DPGME), simulants of sarin nerve gas and nitrogen mustard, respectively., Authors want to thank Spanish Ministry of Economy and Competitiveness for supporting the project TEC2013-48147-C6-4-R

Published
2014

73. New SH-SAW sensor based on sensitive graphene oxide layers for gases or liquids detection

Author

Sayago, I., Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, Carmen, and Muñoz, Edgar

Subjects
Sensor acoustic wave, SAW, Gas sensors, Graphene oxide
Abstract

Poster presented at the XXX Trobades Científiques de la Mediterrània, Josep Miquel Vidal, Graphene and related materials: production, characterization, applications. 15th - 17th october, 2014, Menorca (Spain)., Surface acoustic wave (SAW) sensors have high sensitivity, high stability and signal easy to process. In order to achieve high sensitivity in SAW sensors, it is essential to confine the maximum amount of acoustic energy near the surface of the substrate and minimize wave scattering into the bulk of the substrate. These devices are based on the excitation of shear horizontal surface acoustic waves (SH-SAW) in a piezoelectric substrate, guided by a layer deposited over it and can be used for gas/liquid detection. A key issue in their design is the choice of sensitive layer. Gaphene oxide (GO) is a very attractive nanomaterial for sensor applications because it combines 2D structural features of graphene and the presence of oxygen-containing functional groups (mainly, epoxide, hydroxyl and carbonyl groups), which can potentially interact with a great variety of analytes. Besides, GO can act as a substrate and to be interfaced with various biomolecules and cells, therefore these SH-SAW sensors could be also used to biological detection. In this work, we present the first results obtained with a GO SH-SAW sensor for the detection of (CWA) simulants .

Published
2014

74. As amnistias fiscais como instrumento de política fiscal

Author

Santos, José Pedro Paixão Pereira dos and Nogueira, João Félix

Subjects
Ciências Sociais::Direito [Domínio/Área Científica]
Abstract

Submitted by Cristina Afonso (cac@lisboa.ucp.pt) on 2014-12-09T10:04:35Z No. of bitstreams: 1 As Amnistias Fiscais como Instrumento de Política Fiscal.pdf: 641125 bytes, checksum: dbf24b3daac0ac1d395b5dbfe1ddbceb (MD5) Approved for entry into archive by Cristina Afonso (cac@lisboa.ucp.pt) on 2014-12-09T10:04:43Z (GMT) No. of bitstreams: 1 As Amnistias Fiscais como Instrumento de Política Fiscal.pdf: 641125 bytes, checksum: dbf24b3daac0ac1d395b5dbfe1ddbceb (MD5) Made available in DSpace on 2014-12-09T10:04:43Z (GMT). No. of bitstreams: 1 As Amnistias Fiscais como Instrumento de Política Fiscal.pdf: 641125 bytes, checksum: dbf24b3daac0ac1d395b5dbfe1ddbceb (MD5) Previous issue date: 2014-05-20

Published
2014

75. A wireless and portable electronic nose to differentiate musts of different ripeness degree and grape varieties

Author

Consejo Superior de Investigaciones Científicas (España), Ministerio de Economía y Competitividad (España), Aleixandre, Manuel, Santos, José Pedro, Sayago, Isabel, Cabellos Caballero, Mariano, Arroyo, Teresa, Horrillo, Carmen, Consejo Superior de Investigaciones Científicas (España), Ministerio de Economía y Competitividad (España), Aleixandre, Manuel, Santos, José Pedro, Sayago, Isabel, Cabellos Caballero, Mariano, Arroyo, Teresa, and Horrillo, Carmen

Abstract

Two novel applications using a portable and wireless sensor system (e-nose) for the wine producing industry—The recognition and classification of musts coming from different grape ripening times and from different grape varieties—Are reported in this paper. These applications are very interesting because a lot of varieties of grapes produce musts with low and similar aromatic intensities so they are very difficult to distinguish using a sensory panel. Therefore the system could be used to monitor the ripening evolution of the different types of grapes and to assess some useful characteristics, such as the identification of the grape variety origin and to prediction of the wine quality. Ripening grade of collected samples have been also evaluated by classical analytical techniques, measuring physicochemical parameters, such as, pH, Brix, Total Acidity (TA) and Probable Grade Alcoholic (PGA). The measurements were carried out for two different harvests, using different red (Barbera, Petit Verdot, Tempranillo, and Touriga) and white (Malvar, Malvasía, Chenin Blanc, and Sauvignon Blanc) grape musts coming from the experimental cellar of the IMIDRA at Madrid. Principal Component Analysis (PCA) and Probabilistic Neural Networks (PNN) have been used to analyse the obtained data by e-nose. In addition, and the Canonical Correlation Analysis (CCA) method has been carried out to correlate the results obtained by both technologies. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

Published
2015

76. New SH-SAW sensor based on sensitive graphene oxide layers for gases or liquids detection

Author

Sayago, Isabel, Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, Carmen, Muñoz, Edgar, Sayago, Isabel, Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, Carmen, and Muñoz, Edgar

Abstract

Surface acoustic wave (SAW) sensors have high sensitivity, high stability and signal easy to process. In order to achieve high sensitivity in SAW sensors, it is essential to confine the maximum amount of acoustic energy near the surface of the substrate and minimize wave scattering into the bulk of the substrate. These devices are based on the excitation of shear horizontal surface acoustic waves (SH-SAW) in a piezoelectric substrate, guided by a layer deposited over it and can be used for gas/liquid detection. A key issue in their design is the choice of sensitive layer. Gaphene oxide (GO) is a very attractive nanomaterial for sensor applications because it combines 2D structural features of graphene and the presence of oxygen-containing functional groups (mainly, epoxide, hydroxyl and carbonyl groups), which can potentially interact with a great variety of analytes. Besides, GO can act as a substrate and to be interfaced with various biomolecules and cells, therefore these SH-SAW sensors could be also used to biological detection. In this work, we present the first results obtained with a GO SH-SAW sensor for the detection of (CWA) simulants .

Published
2014

77. Love-wave sensors based in graphene oxide for the detection of chemical warfare agent simulants

Author

Ministerio de Economía y Competitividad (España), Sayago, Isabel, Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, M. C., Muñoz, Edgar, Ministerio de Economía y Competitividad (España), Sayago, Isabel, Matatagui, Daniel, Fernández, María Jesús, Fontecha, J. L., Santos, José Pedro, Horrillo, M. C., and Muñoz, Edgar

Abstract

Graphene oxide (GO) is a very attractive nanomaterial for sensor applications as it combines 2D structural features of graphene and the presence of oxygen-containing functional groups (mainly, epoxide, hydroxyl and carbonyl groups) (1,2) which can potentially interact with a great variety of analytes. Besides, GO offers promise for its use as substrate to be interfaced with biomolecules and cells for biological detection. Recent studies have focused on the applications of the GO in resistive sensors for the detection of pollutant gases (such as CO2, NH3, H2, NO), chemical warfare agent (CWAs) and explosives (3,4). However, to the best of our knowledge, GO has hardly been used in SAW or Love-wave sensors (5). We have developed a Love-wave SAW sensor with three-layer structure consists in ST-cut quartz as substrate, SiO2 as guiding layer and GO as sensitive layer. In this work, we present the first results obtained with GO Love-SAW sensor for the detection of CWA simulants. The sensor detected very low concentrations of dimethyl-methylphosphonate (DMMP) and dipropylene glycol monomethyl ether (DPGME), simulants of sarin nerve gas and nitrogen mustard, respectively.

Published
2014

79. Antimicrobial resistance and genomic rep-PCR fingerprints of Pseudomonas aeruginosa strains from animals on the background of the global population structure.

Author

Serrano, Isa, Oliveira, Manuela, Santos, José Pedro, Bilocq, Florence, Leitão, Alexandre, Tavares, Luis, Pirnay, Jean-Paul, and De Vos, Daniel

Subjects
ANTI-infective agents, DRUG resistance in bacteria, PSEUDOMONAS aeruginosa, BACTERIAL genomes, POLYMERASE chain reaction
Abstract

Background: Pseudomonas aeruginosa is an important human opportunistic pathogen responsible for fatal nosocomial infections worldwide, and has emerged as a relevant animal pathogen. Treatment options are dramatically decreasing, due to antimicrobial resistance and the microorganism's large versatile genome. Antimicrobial resistance profiles, serotype frequency and genomic profile of unrelated P. aeruginosa isolates of veterinary origin (n = 73), including domesticated, farm, zoo and wild animals mainly from Portugal were studied. The genomic profile, determined by DiversiLab system (Rep-PCR-based technique), was compared with the P. aeruginosa global population structure to evaluate their relatedness. Results: Around 40% of the isolates expressed serotypes O6 (20.5%) and O1 (17.8%). A total of 46.6% of isolates was susceptible to all antimicrobials tested. Isolates obtained from most animals were non-multidrug resistant (86.3%), whereas 11% were multidrug resistant, MDR (non-susceptible to at least one agent in ≥ three antimicrobial categories), and 2.7% extensively drug resistant, XDR (non-susceptible to at least one agent in all but two or fewer antimicrobial categories). Resistance percentages were as follows: amikacin (0.0%), aztreonam (41.1%), cefepime (9.6%), ceftazidime (2.7%), ciprofloxacin (15.1%), colistin (0.0%), gentamicin (12.3%), imipenem (1.4%), meropenem (1.4%), piperacillin + tazobactam (12.3%), ticarcillin (16.4%), ticarcillin + clavulanic acid (17.8%), and tobramycin (1.4%). Animal isolates form a population with a non-clonal epidemic structure indistinguishable from the global P. aeruginosa population structure, where no specific 'animal clonal lineage' was detected. Conclusions: Serotypes O6 and O1 were the most frequent. Serotype frequency and antimicrobial resistance patterns found in P. aeruginosa from animals were as expected for this species. This study confirms earlier results that P. aeruginosa has a non-clonal population structure, and shows that P. aeruginosa population from animals is homogeneously scattered and indistinguishable from the global population structure. [ABSTRACT FROM AUTHOR]

Published
2017
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82. Nanocrystalline Tin Oxide Nanofibers Deposited by a Novel Focused Electrospinning Method. Application to the Detection of TATP Precursors.

Author

Santos, José Pedro, Fernández, Maria Jesús, Fontecha, José Luis, Matatagui, Daniel, Sayago, Isabel, Horrillo, Maria Carmen, and Gracia, Isabel

Subjects
*TIN oxides, *NANOFIBERS, *ELECTROSPINNING, *ANNEALING of metals, *DETECTORS, *HYDROGEN peroxide
Abstract

A new method of depositing tin dioxide nanofibers in order to develop chemical sensors is presented. It involves an electrospinning process with in-plane electrostatic focusing over micromechanized substrates. It is a fast and reproducible method. After an annealing process, which can be performed by the substrate heaters, it is observed that the fibers are intertwined forming porous networks that are randomly distributed on the substrate. The fiber diameters oscillate from 100 nm to 200 nm and fiber lengths reach several tens of microns. Each fiber has a polycrystalline structure with multiple nano-grains. The sensors have been tested for the detection of acetone and hydrogen peroxide (precursors of the explosive triacetone triperoxide, TATP) in air in the ppm range. High and fast responses to these gases have been obtained. [ABSTRACT FROM AUTHOR]

Published
2014
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83. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents.

Author

Matatagui, Daniel, Fontecha, José Luis, Fernández, María Jesús, Gràcia, Isabel, Cané, Carles, Santos, José Pedro, and Horrillo, María Carmen

Subjects
BIOLOGICAL warfare research, MICROFLUIDIC devices, MICROPROCESSORS, MONOCLONAL antibodies, IMMUNOGLOBULIN G
Abstract

The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved. [ABSTRACT FROM AUTHOR]

Published
2014
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84. Relevance of Drift Components and Unit-to-Unit Variability in the Predictive Maintenance of Low-Cost Electrochemical Sensor Systems in Air Quality Monitoring.

Author

Tancev, Georgi and Santos, José Pedro

Subjects
*AIR quality monitoring, *ELECTROCHEMICAL sensors, *GAS detectors, *MONTE Carlo method, *POSITION sensors, *CALIBRATION, *MAINTAINABILITY (Engineering)
Abstract

As key components of low-cost sensor systems in air quality monitoring, electrochemical gas sensors have recently received a lot of interest but suffer from unit-to-unit variability and different drift components such as aging and concept drift, depending on the calibration approach. Magnitudes of drift can vary across sensors of the same type, and uniform recalibration intervals might lead to insufficient performance for some sensors. This publication evaluates the opportunity to perform predictive maintenance solely by the use of calibration data, thereby detecting the optimal moment for recalibration and improving recalibration intervals and measurement results. Specifically, the idea is to define confidence regions around the calibration data and to monitor the relative position of incoming sensor signals during operation. The emphasis lies on four algorithms from unsupervised anomaly detection—namely, robust covariance, local outlier factor, one-class support vector machine, and isolation forest. Moreover, the behavior of unit-to-unit variability and various drift components on the performance of the algorithms is discussed by analyzing published field experiments and by performing Monte Carlo simulations based on sensing and aging models. Although unsupervised anomaly detection on calibration data can disclose the reliability of measurement results, simulation results suggest that this does not translate to every sensor system due to unfavorable arrangements of baseline drifts paired with sensitivity drift. [ABSTRACT FROM AUTHOR]

Published
2021
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85. A Novel Reduced Graphene Oxide Modified Carbon Paste Electrode for Potentiometric Determination of Trihexyphenidyl Hydrochloride in Pharmaceutical and Biological Matrices.

Author

Radić, Josip, Buljac, Maša, Genorio, Boštjan, Gričar, Ema, Kolar, Mitja, Sayago, Isabel, Santos, José Pedro, and Polichetti, Tiziana

Subjects
CARBON electrodes, GRAPHENE oxide, ELECTROACTIVE substances, CARBON oxides, DRUG receptors, GRAPHITE oxide
Abstract

A novel promising carbon paste electrode with excellent potentiometric properties was prepared for the analysis of trihexyphenidyl hydrochloride (THP), the acetylcholine receptor and an anticholinergic drug in real samples. It contains 10.2% trihexyphenidy-tetraphenylborate ionic pair as the electroactive material, with the addition of 3.9% reduced graphene oxide and 0.3% of anionic additive into the paste, which consists of 45.0% dibutylphthalate as the solvent mediator and 40.6% graphite. Under the optimized experimental conditions, the electrode showed a Nernstian slope of 58.9 ± 0.2 mV/decade with a regression coefficient of 0.9992. It exhibited high selectivity and reproducibility as well as a fast and linear dynamic response range from 4.0 × 10−7 to 1.0 × 10−2 M. The electrode remained usable for up to 19 days. Analytical applications showed excellent recoveries ranging from 96.8 to 101.7%, LOD was 2.5 × 10−7 M. The electrode was successfully used for THP analysis of pharmaceutical and biological samples. [ABSTRACT FROM AUTHOR]

Published
2021
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86. Resistive gas sensors based on MoS2 nanosheets with high response to low NO2 concentrations

Author

José Pedro Santos, Isabel Sayago, Sean P. Ogilvie, Matthew Large, Rosa Garriga, Edgar Muñoz, J.L. Sanjurjo, Carlos Sánchez-Vicente, A. Amorim Graf, H.J. Wood, A.B. Dalton, Ministerio de Ciencia e Innovación (España), European Commission, Sayago, I. [0000-0002-5917-9469], Sánchez-Vicente, Carlos [0000-0002-7665-1075], Santos, José Pedro [0000-0002-4181-5148], Ogilvie, Sean P. [0000-0002-0433-8186], Large, Matthew J. [0000-0001-7295-7619], Dalton, Alan B. [0000-0001-8043-1377], Garriga, Rosa [0000-0003-2607-7834], Muñoz, Edgar [0000-0001-9309-2394], Sayago, I., Sánchez-Vicente, Carlos, Santos, José Pedro, Ogilvie, Sean P., Large, Matthew J., Dalton, Alan B., Garriga, Rosa, and Muñoz, Edgar

Subjects
Resistive touchscreen, Materials science, business.industry, NO2, Nanomaterials, Drop casting, chemistry.chemical_compound, Membrane, Silicon nitride, chemistry, Optoelectronics, MoS2, business, Resistive gas sensors, Drop-casting, Nanosheet
Abstract

Talk delivered at the 13th Spanish Conference on Electron Devices, CDE 2021, Sevilla (Spain) 9 June 2021 - 11 June 2021, 171142., This work reports on two-dimensional MoS 2 nanomaterial-based resistive gas sensors and their response to sub-ppm NO 2 concentrations. The sensitive material was prepared by drop-casting MoS 2 nanosheet dispersions on silicon nitride suspended membranes. The sensor response was studied at operating temperatures up to 300 °C. The fabricated sensors provided good responses to NO 2 concentrations as low as 20 ppb at room temperature. The n-type MoS 2 sensing mechanism is here discussed., 10.13039/501100004837-Spanish Ministry of Science and Innovation (Grant Number: PID2019-107697RB-C43)

Published
2021
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