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991.
Antonio Anax Falcão de Oliveira Tiago Franco de Oliveira Michelle Francini Dias Marisa Helena Gennari Medeiros Paolo Di Mascio Mariana Veras Miriam Lemos Tania Marcourakis Paulo Hilário Nascimento Saldiva Ana Paula Melo Loureiro 《Particle and fibre toxicology》2018,15(1):40
Background
The Metropolitan Area of São Paulo has a unique composition of atmospheric pollutants, and positive correlations between exposure and the risk of diseases and mortality have been observed. Here we assessed the effects of ambient fine particulate matter (PM2.5) on genotoxic and global DNA methylation and hydroxymethylation changes, as well as the activities of antioxidant enzymes, in tissues of AJ mice exposed whole body to ambient air enriched in PM2.5, which was concentrated in a chamber near an avenue of intense traffic in São Paulo City, Brazil.Results
Mice exposed to concentrated ambient PM2.5 (1 h daily, 3 months) were compared to in situ ambient air exposed mice as the study control. The concentrated PM2.5 exposed group presented increased levels of the oxidized nucleoside 8-oxo-7,8-dihydro-2′-deoxyguanosine in lung and kidney DNA and increased levels of the etheno adducts 1,N6-etheno-2′-deoxyadenosine and 1,N2-etheno-2′-deoxyguanosine in kidney and liver DNA, respectively. Apart from the genotoxic effects, the exposure to PM2.5 led to decreased levels of the epigenetic mark 5-hydroxymethylcytosine (5-hmC) in lung and liver DNA. Changes in lung, liver, and erythrocyte antioxidant enzyme activities were also observed. Decreased glutathione reductase and increased superoxide dismutase (SOD) activities were observed in the lungs, while the liver presented increased glutathione S-transferase and decreased SOD activities. An increase in SOD activity was also observed in erythrocytes. These changes are consistent with the induction of local and systemic oxidative stress.Conclusions
Mice exposed daily to PM2.5 at a concentration that mimics 24-h exposure to the mean concentration found in ambient air presented, after 3 months, increased levels of DNA lesions related to the occurrence of oxidative stress in the lungs, liver, and kidney, in parallel to decreased global levels of 5-hmC in lung and liver DNA. Genetic and epigenetic alterations induced by pollutants may affect the genes committed to cell cycle control, apoptosis, and cell differentiation, increasing the chance of cancer development, which merits further investigation.992.
Helena Windemann Peter Meier und Erich Baumgartner 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1986,183(1):26-32
Zusammenfassung Zur Erkennung und Bestimmung von Weizengliadinbeimischungen in unerhitzten glutenfreien Lebensmitteln können immunologische Methoden wie ELISA herangezogen werden. Werden solche Lebensmittel jedoch über 80 °C erhitzt, so versagen — wohl infolge von Denaturierungsphänomenen — diese Bestimmungsmethoden je nach Hitzebelastung teilweise bis vollständig.Die RP-HPLC-Auftrennung der in 70%igem Ethanol löslichen Proteine spiegelt die Veränderungen wieder, welche diese bei der Hitzebehandlung erfahren. Namentlich treten in Chromatogrammen von erhitzten Weizenproteinen Peaks neu oder verstärkt auf, die für die Erhitzung charakteristisch sind. Bei der üblichen Hitzebehandlung (Walzentrocknung mit und ohne Hitzevorbehandlung, Extrusion) läßt sich anhand dieser Peaks eine Beimischung von 2% Brotweizenmehl erkennen. Gleichzeitig lassen sich auf diese Weise auch Hartweizen- (T. durum) und Roggenmehl mit analoger Empfindlichkeit erfassen. Störungen durch Komponenten glutenfreier Lebensmittel konnten keine festgestellt werden. Einzig bei Produkten mit einem Anteil von über 50% Magermilchpulver kann allerdings erst ein 5% Mehlzusatz erkannt werden.Die alkoholischen Extrakte werden zur Erhöhung der Empfindlichkeit mittels Gefriertrocknung konzentriert. Auf diese Weise werden jedoch die Gliadine durch andere alkohollöslichen Nahrungsmittelkomponenten relativ verdünnt. Dies kann sich einerseits auf die Empfindlichkeit des Nachweises auswirken, andererseits wird dadurch die quantitative Bestimmung anhand der Peakflächen der Gliadine erschwert. Auf die Möglichkeit einer selektiveren Anreicherungsmethode wird hingewiesen. Mit der HPLC-Auftrennung der erhitzten Gliadine ist es möglich geworden, die glutenfreien Lebensmittel generell und mit befriedigender Sicherheit auf die Anwesenheit von Weizen und Roggen zu prüfen.
Detection of wheat gliadins in heated foods by reversed-phase high-performance liquid chromatography
Summary To recognise and determine the wheat gliadins in unheated gluten-free food for coeliac patients the immunological methods such as ELISA can be used. In heated food (above 80°–90 °C) these methods fail wholly or in part to achieve the quantitative determination of wheat gliadin.The changes in protein patterns after heat treatment are also revealed by the RP-HPLC of wheat gliadin and some peaks appear, which are characteristic for heat treated wheat flour. Using these peaks, about 2% admixture of wheat flour (T. aestivum, T. durum) as well as of rye flour can be detected. In foods which contain more than 50% skim milk the addition of only at least 5% of these flours can be detected.The ethanolic extracts of foods were concentrated by freeze-drying prior to analysis by HPLC. The ethanol-soluble non-dialysable food components affect the quantitative determination of wheat or rye proteins by means of peak areas. Selective enrichment is a possibility. The RP-HPLC-analysis of ethanol-soluble proteins makes it possible to detect heated flours of wheat and rye (cooked, roller-dryed, extrusion-cooked) in glutenfree food.相似文献
993.
Helena M. Mentis Madhu Reddy Mary Beth Rosson 《Computer Supported Cooperative Work (CSCW)》2013,22(1):33-63
The design of systems and mechanisms for the development of emotion awareness between communicators has been a concern in CSCW. The typical approach in design is tied up in notions of mediated communication being a ‘poor’ transmitter of crucial emotion information. Thus, by conveying emotion expressions, emotion awareness is consequently supported. In this paper we argue that emotion awareness is also reliant on strategic concealment of emotion expressions through hiding and suppression. To support our argument we present data from a field study of the expression of emotion between healthcare personnel in an emergency room. We provide evidence of the hiding and suppression of emotion expressions by both expressers and observers and how these behaviors support the development of emotion awareness. We then outline a new system design perspective for emotion awareness including both conveyance and concealment behavior and provide examples of systems that have successfully embodied notions of hiding and suppression. 相似文献
994.
Design Contribution to the Competitive Performance of SMEs: The Role of Design Innovation Capabilities
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Paolo Landoni Claudio Dell'Era Gregorio Ferraloro Mattia Peradotto Helena Karlsson Roberto Verganti 《Creativity & Innovation Management》2016,25(4):484-499
The strategic role of design‐driven innovation is being increasingly recognized. Many studies show that investments in design positively influence the innovative capacity of firms and consequently their competitive performance. However, few researchers have explored how this relationship comes about. The studies that over the years have contributed to the understanding of design have identified two main barriers: the lack of a common language on design, and poor analysis of the dynamics that characterize the relationship between investment in design and competitive performance. In this paper, we investigate six small and medium‐sized enterprises (SMEs) located in the Lombardy region of Italy that have received funding from a policy aimed to develop design innovation capabilities. We identify and discuss five different design innovation capabilities and we analyse their role in mediating the relationship between investment in design and competitive performance. 相似文献
995.
Rodrigues José A. Pimenta Sara Pereira José P. Gomes Nuno M. Souto Márcio R. Fernandes Helena C. Caetano Inês Soares-Cunha Carina Oliveira João F. Ribeiro João F. Correia José H. 《Microsystem Technologies》2021,27(1):37-46
Microsystem Technologies - This paper presents the fabrication of a silicon neural probe using low-cost microfabrication technologies, such as thin-films deposition, blade dicing, and... 相似文献
996.
Armejach Adrià Caminal Helena Cebrian Juan M. Langarita Rubén González-Alberquilla Rekai Adeniyi-Jones Chris Valero Mateo Casas Marc Moretó Miquel 《The Journal of supercomputing》2020,76(3):2039-2062
The Journal of Supercomputing - Data-level parallelism is frequently ignored or underutilized. Achieved through vector/SIMD capabilities, it can provide substantial performance improvements on top... 相似文献
997.
Mohsen Besharat Reza Tarinejad Mohammad Taghi Aalami Helena M. Ramos 《Water Resources Management》2016,30(8):2687-2702
Air chambers show good ability in controlling the pressure surge from a water hammer (WH) phenomenon. To simulate an air chamber and study the behavior of air inside it, a compressed air vessel (CAV) is considered in a pressurized system. The current work consists of experimental tests and one-dimensional (1D) and two-dimensional (2D) computational fluid dynamics (CFD) simulations for an air pocket within a CAV in the case of rapid pressurization and the occurrence of WH in a pressurized system. The pressure variations create vorticity and turbulence with oscillating behaviors, but the available 1D models are unable to simulate those phenomena adequately. Therefore, by using the measured data, proper CFD analysis is conducted considering the effect of the wall, y + , mesh size, turbulence, and the wall treatment method to better understand the behavior of the system. Results of the CFD simulation show that realizable k-ε turbulence model, when coupled with the enhanced wall treatment (EWT) method, works adequately for modeling the pressure oscillation. The volume of fluid (VOF) model and the piecewise linear interface calculation (PLIC) method have presented good ability in the prediction of the air-water interface. 相似文献
998.
Most demonstrations of the validity of Internet-based research methods are based on replications of well-known experimental phenomena on the Internet. However, in order to test whether the lack of control over the experimental conditions usually found in Internet studies has an effect on the quality of data, it would be more interesting to show that the Internet cannot only be used to replicate common and well-documented effects, but also less-known experimental findings or elusive phenomena that tend to occur only in very specific conditions. The present experiment explores one such effect, namely augmentation in associative learning, and shows that it can be readily found in the laboratory and on the Internet. 相似文献
999.
Helena Lindgren 《User Modeling and User-Adapted Interaction》2011,21(4-5):377-406
A set of evidence-based clinical practice guidelines has been synthesized and integrated in the clinical decision support system DMSS-R (Dementia Management and Support System) to support clinical routines and reasoning processes as performed by individual health professionals in daily practice. DMSS-R provides advice, tailored to individual and often exceptional patient cases, to the user while providing guidance to the next step in the assessments and support for hypothesis generation and evaluation throughout the process. This paper describes DMSS-R and the results of a case study in clinical practice where the system was used. The case study included interviews and observations of the clinical investigation process as undertaken in 41 real patient cases with suspected dementia. Two physicians participated, one of whom was considered a novice regarding dementia while the other had a moderate level of skills. Initially, both physicians were unfamiliar with DMSS-R. A group of nurses together with care personnel and relatives were also involved. The most important contribution of DMSS-R at the point of care, apart from the tailored explanatory support related to a patient case, was the educational support it provided. This was partly manifested in a change of routines in the encounter with patients. Aspects regarding the individual health care professional??s need for a personalized support system are discussed and put in relation to the team??s need for support, and in relation to the diversity of disease manifestations in this group of patients, which reinforces patient-centric assessments. 相似文献
1000.
HPLC‐DAD,ESI–MS/MS,and NMR of Lycopene Isolated From P. guajava L. and Its Biotechnological Applications
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Adriany G. N. Amorim Jessica M. T. Souza Raimunda C. Santos Beatriz Gullón Ana Oliveira Luiz F. A. Santos Adamor L. E. Virgino Ana C. Mafud Helena M. Petrilli Yvonne P. Mascarenhas Cristina Delerue‐Matos Manuela E. Pintado José R. S. A. Leite 《European Journal of Lipid Science and Technology》2018,120(3)