Signal Subspace Identification in Hyperspectral Linear Mixtures

Chpater in Book Proceedings with Peer Review Second Iberian Conference, IbPRIA 2005, Estoril, Portugal, June 7-9, 2005, Proceedings, Part II

Tuberculosis and latent tuberculosis in prison inmates

OBJECTIVE: To estimate the prevalences of tuberculosis and latent tuberculosis in inmates. METHODS: Observational study was carried out with inmates of a prison and a jail in the State of São Paulo, Southeastern Brazil, between March and December of 2008. Questionnaires were used to collect sociodemographic and epidemiological data. Tuberculin skin testing was administered (PPD-RT23-2TU/0.1 mL), and the following laboratory tests were also performed: sputum smear examination, sputum culture, identification of strains isolated and drug susceptibility testing. The variables were compared using Pearson's chi-square (Χ2) association test, Fisher's exact test and the proportion test. RESULTS: Of the 2,435 inmates interviewed, 2,237 (91.9%) agreed to submit to tuberculin skin testing and of these, 73.0% had positive reactions. The prevalence of tuberculosis was 830.6 per 100,000 inmates. The coefficients of prevalence were 1,029.5/100,000 for inmates of the prison and 525.7/100,000 for inmates of the jail. The sociodemographic characteristics of the inmates in the two groups studied were similar; most of the inmates were young and single with little schooling. The epidemiological characteristics differed between the prison units, with the number of cases of previous tuberculosis and of previous contact with the disease greater in the prison and coughing, expectoration and smoking more common in the jail. Among the 20 Mycobacterium tuberculosis strains identified, 95.0% were sensitive to anti-tuberculosis drugs, and 5.0% were resistant to streptomycin. CONCLUSIONS: The prevalences of tuberculosis and latent tuberculosis were higher in the incarcerated population than in the general population, and they were also higher in the prison than in the jail.

Contribution of hospital effluents to the load of pharmaceuticals in urban wastewaters: Identification of ecologically relevant pharmaceuticals

The impact of effluent wastewaters from four different hospitals: a university (1456 beds), a general (350 beds), a pediatric (110 beds) and a maternity hospital (96 beds), which are conveyed to the same wastewater treatment plant (WWTP), was evaluated in the receiving urban wastewaters. The occurrence of 78 pharmaceuticals belonging to several therapeutic classes was assessed in hospital effluents and WWTP wastewaters (influent and effluent) as well as the contribution of each hospital in WWTP influent in terms of pharmaceutical load. Results indicate that pharmaceuticals are widespread pollutants in both hospital and urban wastewaters. The contribution of hospitals to the input of pharmaceuticals in urban wastewaters widely varies, according to their dimension. The estimated total mass loadings were 306 g d− 1 for the university hospital, 155 g d− 1 for the general one, 14 g d− 1 for the pediatric hospital and 1.5 g d− 1 for the maternity hospital, showing that the biggest hospitals have a greater contribution to the total mass load of pharmaceuticals. Furthermore, analysis of individual contributions of each therapeutic group showed that NSAIDs, analgesics and antibiotics are among the groups with the highest inputs. Removal efficiency can go from over 90% for pharmaceuticals like acetaminophen and ibuprofen to not removal for β-blockers and salbutamol. Total mass load of pharmaceuticals into receiving surface waters was estimated between 5 and 14 g/d/1000 inhabitants. Finally, the environmental risk posed by pharmaceuticals detected in hospital and WWTP effluents was assessed by means of hazard quotients toward different trophic levels (algae, daphnids and fish). Several pharmaceuticals present in the different matrices were identified as potentially hazardous to aquatic organisms, showing that especial attention should be paid to antibiotics such as ciprofloxacin, ofloxacin, sulfamethoxazole, azithromycin and clarithromycin, since their hazard quotients in WWTP effluent revealed that they could pose an ecotoxicological risk to algae.

Brewer's spent grain from different types of malt: Evaluation of the antioxidant activity and identification of the major phenolic compounds

The antioxidant activity and phenolic composition of brewer's spent grain (BSG) extracts obtained by microwave-assisted extraction from twomalt types (light and darkmalts) were investigated. The total phenolic content (TPC) and antioxidant activity among the light BSG extracts (pilsen, melano, melano 80 and carared)were significantly different (p b 0.05) compared to dark extracts (chocolate and black types), with the pilsen BSG showing higher TPC (20 ± 1 mgGAE/g dry BSG). In addition, the antioxidant activity assessed by 2,2-diphenyl- 1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and deoxyribose assays decreased as a result of increasing kilning temperatures in the following order: pilsen N melano N melano 80 N carared N chocolate N black. HPLC-DAD/ESI-MS/MS analysis indicated the presence of phenolic acids, such as ferulic, p-coumaric and syringic acids, as well as several isomeric ferulate dehydrodimers and one dehydrotrimer. Chocolate and black extracts, obtained frommalts submitted to the highest kilning temperatures, showed the lowest levels of ferulic and p-coumaric acids. These results suggested that BSG extracts from pilsen malt might be used as an inexpensive and good natural source of antioxidants with potential interest for the food, pharmaceutical and/or cosmetic industries after purification.

PAH air pollution at a Portuguese urban area: carcinogenic risks and sources identification

This study aimed to characterize air pollution and the associated carcinogenic risks of polycyclic aromatic hydrocarbon (PAHs) at an urban site, to identify possible emission sources of PAHs using several statistical methodologies, and to analyze the influence of other air pollutants and meteorological variables on PAH concentrations.The air quality and meteorological data were collected in Oporto, the second largest city of Portugal. Eighteen PAHs (the 16 PAHs considered by United States Environment Protection Agency (USEPA) as priority pollutants, dibenzo[a,l]pyrene, and benzo[j]fluoranthene) were collected daily for 24 h in air (gas phase and in particles) during 40 consecutive days in November and December 2008 by constant low-flow samplers and using polytetrafluoroethylene (PTFE) membrane filters for particulate (PM10 and PM2.5 bound) PAHs and pre-cleaned polyurethane foam plugs for gaseous compounds. The other monitored air pollutants were SO2, PM10, NO2, CO, and O3; the meteorological variables were temperature, relative humidity, wind speed, total precipitation, and solar radiation. Benzo[a]pyrene reached a mean concentration of 2.02 ngm−3, surpassing the EU annual limit value. The target carcinogenic risks were equal than the health-based guideline level set by USEPA (10−6) at the studied site, with the cancer risks of eight PAHs reaching senior levels of 9.98×10−7 in PM10 and 1.06×10−6 in air. The applied statistical methods, correlation matrix, cluster analysis, and principal component analysis, were in agreement in the grouping of the PAHs. The groups were formed according to their chemical structure (number of rings), phase distribution, and emission sources. PAH diagnostic ratios were also calculated to evaluate the main emission sources. Diesel vehicular emissions were the major source of PAHs at the studied site. Besides that source, emissions from residential heating and oil refinery were identified to contribute to PAH levels at the respective area. Additionally, principal component regression indicated that SO2, NO2, PM10, CO, and solar radiation had positive correlation with PAHs concentrations, while O3, temperature, relative humidity, and wind speed were negatively correlated.

Avaliação da exposição a fungos e partículas em explorações avícolas e suinícolas: estudo

O projeto “Avaliação da Exposição a Fungos e Partículas em Explorações Avícolas e Suinícolas” contemplou um elevado número de colheitas ambientais e biológicas e respectivo processamento laboratorial, sendo apenas possível a sua concretização graças ao financiamento disponibilizado pela Autoridade para as Condições de Trabalho. Foi realizado um estudo transversal para avaliar a contaminação causada por fungos e partículas em 7 explorações avícolas e 7 explorações suinícolas. No que concerne à monitorização biológica, foram medidos os parâmetros espirométricos, utilizando o espirómetro MK8 Microlab, avaliada a existência de sintomas clínicos associados com a asma e outras doenças alérgicas, através de questionário adaptado European Community Respiratory Health Survey e, ainda, avaliada a sensibilização aos agentes fúngicos (IgE). Foram ainda adicionados dois objetivos ao estudo, designadamente: aferir a existência de três espécies/estirpes potencialmente patogénicas/toxinogénicas com recurso à biologia molecular e avaliar a exposição dos trabalhadores à micotoxina aflatoxina B1 por recurso a indicador biológico de exposição. Foram colhidas 27 amostras de ar de 25 litros nas explorações avícolas e 56 de 50 litros nas explorações suinícolas através do método de impacto. As colheitas de ar e a medição da concentração das partículas foram realizadas no interior e no exterior dos pavilhões, sendo este último considerado como local de referência. Simultaneamente, a temperatura e a humidade relativa também foram registadas. As colheitas das superfícies foram realizadas através da técnica de zaragatoa, tendo sido utilizado um quadrado de metal inoxidável de 10 cm de lado, de acordo com a International Standard ISO 18593 – 2004. As zaragatoas obtidas (20 das explorações avícolas e 48 das explorações suinícolas) foram inoculadas em malte de extract agar (2%) com cloranfenicol (0,05 g/L). Além das colheitas de ar e de superfícies, foram também obtidas colheitas da cama das explorações avícolas (7 novas e 14 usadas) e da cobertura do pavimento das explorações suinícolas (3 novas e 4 usadas) e embaladas em sacos esterilizados. Cada amostra foi diluída e inoculada em placas contendo malte extract agar. Todas as amostras foram incubadas a 27,5ºC durante 5 a 7 dias e obtidos resultados quantitativos (UFC/m3; UFC/m2; UFC/g) e qualitativos com a identificação das espécies fúngicas. Para a aplicação dos métodos de biologia molecular foram realizadas colheitas de ar de 300 litros utilizando o método de impinger com a velocidade de recolha de 300 L/min. A identificação molecular de três espécies potencialmente patogénicas e/ou toxinogénicas (Aspergillus flavus, Aspergillus fumigatus e Stachybotrys chartarum) foram obtidas por PCR em tempo real (PCR TR) utilizando o Rotor-Gene 6000 qPCR Detection System. As medições de partículas foram realizadas por recurso a equipamento de leitura direta (modelo Lighthouse, 2016 IAQ). Este recurso permitiu medir a concentração (mg/m3) de partículas em 5 dimensões distintas (PM 0.5; PM 1.0; PM 2.5; PM 5.0; PM10). Nas explorações avícolas, 28 espécies/géneros de fungos foram isolados no ar, tendo Aspergillus versicolor sido a espécie mais frequente (20.9%), seguida por Scopulariopsis brevicaulis (17.0%) e Penicillium sp. (14.1%). Entre o género Aspergillus, Aspergillus flavus apresentou o maior número de esporos (>2000 UFC/m3). Em relação às superfícies, A. versicolor foi detetada em maior número (>3 × 10−2 UFC/m2). Na cama nova, Penicillium foi o género mais frequente (59,9%), seguido por Alternaria (17,8%), Cladosporium (7,1%) e Aspergillus (5,7%). Na cama usada, Penicillium sp. foi o mais frequente (42,3%), seguido por Scopulariopsis sp. (38,3%), Trichosporon sp. (8,8%) e Aspergillus sp. (5,5%). Em relação à contaminação por partículas, as partículas com maior dimensão foram detectadas em maiores concentrações, designadamente as PM5.0 (partículas com a dimensão de 5.0 bm ou menos) e PM10 (partículas com a dimensão de 10 bm ou menos). Neste setting a prevalência da alteração ventilatória obstrutiva foi superior nos indivíduos com maior tempo de exposição (31,7%) independentemente de serem fumadores (17,1%) ou não fumadores (14,6%). Relativamente à avaliação do IgE específico, foi apenas realizado em trabalhadores das explorações avícolas (14 mulheres e 33 homens), não tendo sido encontrada associação positiva (p<0.05%) entre a contaminação fúngica e a sensibilização a antigénios fúngicos. No caso das explorações suinícolas, Aspergillus versicolor foi a espécie mais frequente (20,9%), seguida por Scopulariopsis brevicaulis (17,0%) e Penicillium sp. (14,1%). No género Aspergillus, A. versicolor apresentou o maior isolamento no ar (>2000 UFC/m3) e a maior prevalência (41,9%), seguida por A. flavus e A. fumigatus (8,1%). Em relação às superfícies analisadas, A. versicolor foi detetada em maior número (>3 ×10−2 UFC/m2). No caso da cobertura do pavimento das explorações suinícolas, o género Thicoderma foi o mais frequente na cobertura nova (28,0%) seguida por A. versicolor e Acremonium sp. (14,0%). O género Mucor foi o mais frequente na cobertura usada (25,1%), seguido por Trichoderma sp. (18,3%) e Acremonium sp. (11,2%). Relativamente às partículas, foram evidenciados também valores mais elevados na dimensão PM5 e, predominantes nas PM10. Neste contexto, apenas 4 participantes (22,2%) apresentaram uma alteração ventilatória obstrutiva. Destes, as obstruções mais graves encontraram-se nos que também apresentavam maior tempo de exposição. A prevalência de asma na amostra de trabalhadores em estudo, pertencentes aos 2 contextos em estudo, foi de 8,75%, tendo-se verificado também uma prevalência elevada de sintomatologia respiratória em profissionais não asmáticos. Em relação à utilização complementar dos métodos convencionais e moleculares, é recomendável que a avaliação da contaminação fúngica nestes settings, e, consequentemente, a exposição profissional a fungos, seja suportada pelas duas metodologias e, ainda, que ocorre exposição ocupacional à micotoxina aflatoxina B1 em ambos os contextos profissionais. Face aos resultados obtidos, é importante salientar que os settings alvo de estudo carecem de uma intervenção integrada em Saúde Ocupacional no âmbito da vigilância ambiental e da vigilância da saúde, com o objetivo de diminuir a exposição aos dois factores de risco estudados (fungos e partículas).

Experimental design methodologies for the identification of Michaelis-Menten type kinetics

The main objective of this work was to investigate the application of experimental design techniques for the identification of Michaelis-Menten kinetic parameters. More specifically, this study attempts to elucidate the relative advantages/disadvantages of employing complex experimental design techniques in relation to equidistant sampling when applied to different reactor operation modes. All studies were supported by simulation data of a generic enzymatic process that obeys to the Michaelis-Menten kinetic equation. Different aspects were investigated, such as the influence of the reactor operation mode (batch, fed-batch with pulse wise feeding and fed-batch with continuous feeding) and the experimental design optimality criteria on the effectiveness of kinetic parameters identification. The following experimental design optimality criteria were investigated: 1) minimization of the sum of the diagonal of the Fisher information matrix (FIM) inverse (A-criterion), 2) maximization of the determinant of the FIM (D-criterion), 3) maximization of the smallest eigenvalue of the FIM (E-criterion) and 4) minimization of the quotient between the largest and the smallest eigenvalue (modified E-criterion). The comparison and assessment of the different methodologies was made on the basis of the Cramér-Rao lower bounds (CRLB) error in respect to the parameters vmax and Km of the Michaelis-Menten kinetic equation. In what concerns the reactor operation mode, it was concluded that fed-batch (pulses) is better than batch operation for parameter identification. When the former operation mode is adopted, the vmax CRLB error is lowered by 18.6 % while the Km CRLB error is lowered by 26.4 % when compared to the batch operation mode. Regarding the optimality criteria, the best method was the A-criterion, with an average vmax CRLB of 6.34 % and 5.27 %, for batch and fed-batch (pulses), respectively, while presenting a Km’s CRLB of 25.1 % and 18.1 %, for batch and fed-batch (pulses), respectively. As a general conclusion of the present study, it can be stated that experimental design is justified if the starting parameters CRLB errors are inferior to 19.5 % (vmax) and 45% (Km), for batch processes, and inferior to 42 % and to 50% for fed-batch (pulses) process. Otherwise equidistant sampling is a more rational decision. This conclusion clearly supports that, for fed-batch operation, the use of experimental design is likely to largely improve the identification of Michaelis-Menten kinetic parameters.

Demo: automatic personal identification system for security in critical services: a case study

The demonstration proposal moves from the capabilities of a wireless biometric badge [4], which integrates a localization and tracking service along with an automatic personal identification mechanism, to show how a full system architecture is devised to enable the control of physical accesses to restricted areas. The system leverages on the availability of a novel IEEE 802.15.4/Zigbee Cluster Tree network model, on enhanced security levels and on the respect of all the users' privacy issues.

Validação do método de deteção de eritropoietina recombinante humana em urina humana por focalização isoelétrica

A eritropoietina (EPO) é uma substância que estimula a produção de eritrócitos, aumentando a oxigenação muscular, sendo segregada de forma natural pelo organismo e excretada na urina em baixas concentrações. Devido às suas propriedades e características, a EPO foi rapidamente introduzida no mundo do desporto, como substância ilícita, proporcionando vantagens no rendimento desportivo. No início de 2000 foi desenvolvido um método de deteção direta de EPO Recombinante (rHuEPO) em urina humana por Lasne, baseado na focalização isoelétrica (IEF) em gel de poliacrilamida, seguido de duplo blote, tendo este sido publicado e validado. Em 2002, a Agência Mundial Antidopagem (AMA) implementou este mesmo método, sendo atualmente um dos métodos oficiais utilizado pelos laboratórios acreditados pela AMA. Desta forma, o ponto de partida para a realização deste trabalho consistiu na necessidade de implementar e validar o método de referência de IEF para a deteção de rHuEPO em urina humana. O trabalho foi realizado no Laboratório de Análises e Dopagem (LAD) do Instituto do Desporto de Portugal (IDP), atual Instituto Português do Desporto e Juventude (IPDJ). O principal objetivo deste trabalho consistiu no estudo/investigação de diferentes parâmetros de validação (especificidade/seletividade; capacidade de identificação; limite de deteção; exatidão e repetibilidade), de acordo com o protocolado no Procedimento Geral interno do Laboratório de Análises de Dopagem de Lisboa (LAD). O referido método de triagem e confirmação revelou possuir características de desempenho conformes com os requisitos aplicáveis, pelo que é considerado validado e apto.

Trypanosoma cruzi strains from triatomine collected in Bahia and Rio Grande do Sul, Brazil

OBJECTIVE Collection of triatomines in domestic, peridomestic and sylvatic environments in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil respectively, and isolation of Trypanosoma cruzi strains. METHODS First, the captured triatomines were identified using insect identification keys, then their intestinal content was examined by abdominal compression, and the samples containing trypanosomatid forms were inoculated in LIT medium and Swiss mice. RESULTS Six triatomine species were collected in cities in Bahia, namely Panstrongylus geniculatus (01), Triatoma melanocephala (11), T. lenti (94), T. pseudomaculata (02), T. sherlocki (26) and T. sordida (460), and two in cities in Rio Grande do Sul, namely T. circummaculata (11) and T. rubrovaria (115). Out of the specimens examined, T. cruzi was isolated from 28 triatomine divided into four different species: T. melanocephala (one), T. lenti (one), T. rubrovaria (16) and T. sordida (10). Their index of natural infection by T. cruzi was 6.4%. CONCLUSIONS The isolation of T. cruzi strains from triatomines found in domestic and peridomestic areas shows the potential risk of transmission of Chagas disease in the studied cities. The maintenance of those T. cruzi strains in laboratory is intended to promote studies that facilitate the understanding of the parasite-vector-host relationship.

Characterization and identification of printed objects

A study about the physical appearance of pre-photographic, photomechanical, photographic and digital positive reflective prints was made, relating the obtained images with the history, materials and technology used to create them. The studied samples are from the Image Permanence Institute (IPI) study collection. The digital images were obtained using a digital SLR on a copystand and a compound light microscope, with different lighting angles (0º, 45ºand 90º) and magnifications from overall views on the copystand down to a 20x objective lens on the microscope. Most of these images were originally created by IPI for www.digitalsamplebook.org, a web tool for teaching print identification, and will be used on the www.graphicsatlas.org website, along with textual information on identification, technology and history information about these reproduction processes.

In-situ X-ray diffraction studies during growth of Ni-Ti shape memory alloy films and their complementary ex-situ characterization

Shape Memory Alloy (SMA) Ni-Ti films have attracted much interest as functional and smart materials due to their unique properties. However, there are still important issues unresolved like formation of film texture and its control as well as substrate effects. Thus, the main challenge is not only the control of the microstructure, including stoichiometry and precipitates, but also the identification and control of the preferential orientation since it is a crucial factor in determining the shape memory behaviour. The aim of this PhD thesis is to study the optimisation of the deposition conditions of films of Ni-Ti in order to obtain the material fully crystallized at the end of the deposition, and to establish a clear relationship between the substrates and texture development. In order to achieve this objective, a two-magnetron sputter deposition chamber has been used allowing to heat and to apply a bias voltage to the substrate. It can be mounted into the six-circle diffractometer of the Rossendorf Beamline (ROBL) at the European Synchrotron Radiation Facility (ESRF), Grenoble, France, enabling an in-situ characterization by X-ray diffraction(XRD) of the films during their growth and annealing. The in-situ studies enable us to identify the different steps of the structural evolution during deposition with a set of parameters as well as to evaluate the effect of changing parameters on the structural characteristics of the deposited film. Besides the in-situ studies, other complementary ex-situ characterization techniques such as XRD at a laboratory source, Rutherford backscattering spectroscopy(RBS), Auger electron spectroscopy (AES), cross-sectional transmission electron microscopy (X-TEM), scanning electron microscopy (SEM), and electrical resistivity (ER) measurements during temperature cycling have been used for a fine structural characterization. In this study, mainly naturally and thermally oxidized Si(100) substrates, TiN buffer layers with different thicknesses (i.e. the TiN topmost layer crystallographic orientation is thickness dependent) and MgO(100) single crystals were used as substrates. The chosen experimental procedure led to a controlled composition and preferential orientation of the films. The type of substrate plays an important role for the texture of the sputtered Ni-Ti films and according to the ER results, the distinct crystallographic orientations of the Ni-Ti films influence their phase transformation characteristics.

Viability of the use of thin-film A-SiC:H photodiodes for protein identification

In this paper, we present a multilayer device based on a-Si:H/a-SiC:H that operates as photodetector and optical filter. The use of such device in protein detection applications is relevant in Fluorescence Resonance Energy Transfer (FRET) measurements. This method demands the detection of fluorescent signals located at specific wavelengths bands in the visible part of the electromagnetic spectrum. The device operates in the visible range with a selective sensitivity dependent on electrical and optical bias. Several nanosensors were tested with a commercial spectrophotometer to assess the performance of FRET signals using glucose solutions of different concentrations. The proposed device was used to demonstrate the possibility of FRET signals detection, using visible signals of similar wavelength and intensity. The device sensitivity was tuned to enhance the wavelength band of interest using steady state optical bias at 400 nm. Results show the ability of the device to detect signals in this range. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Virtual laboratory for educational environments

In this paper a new simulation environment for a virtual laboratory to educational proposes is presented. The Logisim platform was adopted as the base digital simulation tool, since it has a modular implementation in Java. All the hardware devices used in the laboratory course was designed as components accessible by the simulation tool, and integrated as a library. Moreover, this new library allows the user to access an external interface. This work was motivated by the needed to achieve better learning times on co-design projects, based on hardware and software implementations, and to reduce the laboratory time, decreasing the operational costs of engineer teaching. Furthermore, the use of virtual laboratories in educational environments allows the students to perform functional tests, before they went to a real laboratory. Moreover, these functional tests allow to speed-up the learning when a problem based approach methodology is considered. © 2014 IEEE.

An internet remote laboratory to teach industrial automation

This paper presents the new internet remote laboratory (IRL), constructed at Mechanical Engineering Department (MED), Instituto Superior de Engenharia de Lisboa (ISEL), to teach Industrial Automation, namely electropneumatic cycles. The aim of this work was the development and implementation of a remote laboratory that was simple and effective from the user point of view, allowing access to all its functionalities through a web browser without having to install any other program and giving access to all the features that the students can find at the physical laboratory. With this goal in mind, it has been implemented a simple architecture with the new programmable logic controller (PLC) SIEMENS S7-1200, and with the aid of several free programs, programming technologies such as JavaScript, PHP and databases, it was possible to have a remote laboratory, with a simple interface, to teach industrial automation students.