993 resultados para Nitrogen Sorption Measurements
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A new biomimetic sensor for leucomalachite green host-guest interactions and potentiometric transduction is presented. The artificial host was imprinted in methacrylic acid or acrylamido-2-methyl-1-propanesulfonic acid-based polymers. Molecularly imprinted particles were dispersed in 2-nitrophenyloctyl ether and trapped in poly(vinyl chloride). The potentiometric sensors exhibited a near-Nernstian response in steady state evaluations, with slopes and detection limits ranging from 45.8 to 81.2 mV and 0.28 to 1.01 , respectively. They were independent from the pH of test solutions within 3 to 5. Good selectivity was observed towards drugs that may contaminate water near fish cultures, such as oxycycline, doxycycline, enrofloxacin, trimethoprim, creatinine, chloramphenicol, and dopamine. The sensors were successfully applied to field monitoring of leucomalachite green in river samples. The method offered the advantages of simplicity, accuracy, applicability to colored and turbid samples, and automation feasibility.
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Graduate Student Symposium on Molecular Imprinting 2013, na Queen’s University, Belfast, United Kingdom, 15 a 17 de Agosto de 2013
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Objective: To compare measurements of the upper arm cross-sectional areas (total arm area,arm muscle area, and arm fat area of healthy neonates) as calculated using anthropometry with the values obtained by ultrasonography. Materials and methods: This study was performed on 60 consecutively born healthy neonates: gestational age (mean6SD) 39.661.2 weeks, birth weight 3287.16307.7 g, 27 males (45%) and 33 females (55%). Mid-arm circumference and tricipital skinfold thickness measurements were taken on the left upper mid-arm according to the conventional anthropometric method to calculate total arm area, arm muscle area and arm fat area. The ultrasound evaluation was performed at the same arm location using a Toshiba sonolayer SSA-250AÒ, which allows the calculation of the total arm area, arm muscle area and arm fat area by the number of pixels enclosed in the plotted areas. Statistical analysis: whenever appropriate, parametric and non-parametric tests were used in order to compare measurements of paired samples and of groups of samples. Results: No significant differences between males and females were found in any evaluated measurements, estimated either by anthropometry or by ultrasound. Also the median of total arm area did not differ significantly with either method (P50.337). Although there is evidence of concordance of the total arm area measurements (r50.68, 95% CI: 0.55–0.77) the two methods of measurement differed for arm muscle area and arm fat area. The estimated median of measurements by ultrasound for arm muscle area were significantly lower than those estimated by the anthropometric method, which differed by as much as 111% (P,0.001). The estimated median ultrasound measurement of the arm fat was higher than the anthropometric arm fat area by as much as 31% (P,0.001). Conclusion: Compared with ultrasound measurements using skinfold measurements and mid-arm circumference without further correction may lead to overestimation of the cross-sectional area of muscle and underestimation of the cross-sectional fat area. The correlation between the two methods could be interpreted as an indication for further search of correction factors in the equations.
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A thesis submitted for the degree of Ph. D. in Physics
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Sorption is commonly agreed to be the major process underlying the transport and fate of polycyclic aromatic hydrocarbons (PAHs) in soils. However, there is still a scarcity of studies focusing on spatial variability at the field scale in particular. In order to investigate the variation in the field of phenanthrene sorption, bulk topsoil samples were taken in a 15 × 15-m grid from the plough layer in two sandy loam fields with different texture and organic carbon (OC) contents (140 samples in total). Batch experiments were performed using the adsorption method. Values for the partition coefficient K d (L kg−1) and the organic carbon partition coefficient K OC (L kg−1) agreed with the most frequently used models for PAH partitioning, as OC revealed a higher affinity for sorption. More complex models using different OC compartments, such as non-complexed organic carbon (NCOC) and complexed organic carbon (COC) separately, performed better than single K OC models, particularly for a subset including samples with Dexter n < 10 and OC <0.04 kg kg−1. The selected threshold revealed that K OC-based models proved to be applicable for more organic fields, while two-component models proved to be more accurate for the prediction of K d and retardation factor (R) for less organic soils. Moreover, OC did not fully reflect the changes in phenanthrene retardation in the field with lower OC content (Faardrup). Bulk density and available water content influenced the phenanthrene transport mechanism phenomenon.
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With the objective to study the variation of optical properties of rat muscle during optical clearing, we have performed a set of optical measurements from that kind of tissue. The measurements performed were total transmittance, collimated transmittance, specular reflectance and total reflectance. This set of measurements is sufficient to determine diffuse reflectance and absorbance of the sample, also necessary to estimate the optical properties. All the performed measurements and calculated quantities will be used later in inverse Monte Carlo (IMC) simulations to determine the evolution of the optical properties of muscle during treatments with ethylene glycol and glucose. The results obtained with the measurements already provide some information about the optical clearing treatments applied to the muscle and translate the mechanisms of turning the tissue more transparent and sequence of regimes of optical clearing.
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Introduction: Highly Active Antiretroviral Therapy (HAART) has improved and extended the lives of thousands of people living with HIV/AIDS around the world. However, this treatment can lead to the development of adverse reactions such as lipoatrophy/lipohypertrophy syndrome (LLS) and its associated risks. Objective: This study was designed to assess the prevalence of self-reported lipodystrophy and nutritional status by anthropometric measurements in patients with HIV/AIDS. Methods: An observational study of 227 adult patients in the Secondary Immunodeficiencies Outpatient Department of Dermatology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (3002 ADEE-HCFMUSP). The sample was divided into three groups; Group 1 = 92 patients on HAART and with self-reported lipodystrophy, Group 2 = 70 patients on HAART without self-reported lipodystrophy and Group 3 = 65 patients not taking HAART. The nutritional status of individuals in the study sample was determined by body mass index (BMI) and percentage of body fat (% BF). The cardiovascular risk and diseases associated with abdominal obesity were determined by waist/hip ratio (WHR) and waist circumference (WC). Results: The prevalence of self-reported lipoatrophy/lipohypertrophy syndrome was 33% among women and 59% among men. Anthropometry showed depletion of fat mass in the evaluation of the triceps (TSF) in the treatment groups with HAART and was statistically independent of gender; for men p = 0.001, and for women p = 0.007. Similar results were found in the measurement of skin folds of the upper and lower body (p = 0.001 and p = 0.003 respectively). In assessing the nutritional status of groups by BMI and % BF, excess weight and body fat were more prevalent among women compared to men (p = 0.726). The WHR and WC revealed risks for cardiovascular and other diseases associated with abdominal obesity for women on HAART and with self-reported LLS (p = 0.005) and (p = 0.011). Conclusions: Anthropometric measurements were useful in the confirmation of the prevalence of LLS. BMI alone does not appear to be a good parameter for assessing the nutritional status of HIV-infected patients on HAART and with LLS. Other anthropometric measurements are needed to evaluate patients with the lipoatrophy/lipohypertrophy syndrome.
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Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica
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Dissertação para obtenção do Grau de Mestre em Engenharia do ambiente, perfil de engenharia sanitária
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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Engenharia Sanitária
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Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica
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O Azoto (N): da ciência para a sociedade é um projecto de comunicação de ciência que tem por objecNvo consciencializar os jovens para as ameaças que o azoto (N) em excesso traz para a humanidade. Pode ser dividido em duas partes. Uma, de invesNgação, sobre a análise de resultados de uma consulta pública realizada entre professores, usando o método qualitaNvo do focus group, para compreender a sua sensibilidade e propostas de solução para minimizar o excesso de N no ambiente. Os resultados obNdos foram instrumentais para o desenvolvimento da segunda parte. Esta segunda parte é uma proposta de projecto a submeter ao Horizon 2020, no âm-‐ bito da “Science with and for Society “. Nela se propõe uma abordagem educaNva trans-‐disciplinar, conseguida através da interacção entre docentes do secundário, e do ensino superior, associação de pais e organizações cívicas não governamentais, com vista à consciencialização dos jovens para as ameaças do N em excesso no meio ambiente, fazendo o enquadramento cien@fico e fornecendo abordagens tecnológi-‐ cas. A inovação desta proposta baseia-‐se: (i) no acompanhamento e desenvolvimen-‐ to profissional dos docentes do secundário, (ii) na moNvação dos estudantes a de-‐ senvolver o seu próprio estudo e pesquisa com a tutoria dos docentes, da escola e do ensino superior, e (iii) no desenvolvimento de capacidades de comunicação dos jo-‐ vens para exercer uma cidadania acNva em prol da minimização das ameaças do N.
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Since the invention of photography humans have been using images to capture, store and analyse the act that they are interested in. With the developments in this field, assisted by better computers, it is possible to use image processing technology as an accurate method of analysis and measurement. Image processing's principal qualities are flexibility, adaptability and the ability to easily and quickly process a large amount of information. Successful examples of applications can be seen in several areas of human life, such as biomedical, industry, surveillance, military and mapping. This is so true that there are several Nobel prizes related to imaging. The accurate measurement of deformations, displacements, strain fields and surface defects are challenging in many material tests in Civil Engineering because traditionally these measurements require complex and expensive equipment, plus time consuming calibration. Image processing can be an inexpensive and effective tool for load displacement measurements. Using an adequate image acquisition system and taking advantage of the computation power of modern computers it is possible to accurately measure very small displacements with high precision. On the market there are already several commercial software packages. However they are commercialized at high cost. In this work block-matching algorithms will be used in order to compare the results from image processing with the data obtained with physical transducers during laboratory load tests. In order to test the proposed solutions several load tests were carried out in partnership with researchers from the Civil Engineering Department at Universidade Nova de Lisboa (UNL).
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The “CMS Safety Closing Sensors System” (SCSS, or CSS for brevity) is a remote monitoring system design to control safety clearance and tight mechanical movements of parts of the CMS detector, especially during CMS assembly phases. We present the different systems that makes SCSS: its sensor technologies, the readout system, the data acquisition and control software. We also report on calibration and installation details, which determine the resolution and limits of the system. We present as well our experience from the operation of the system and the analysis of the data collected since 2008. Special emphasis is given to study positioning reproducibility during detector assembly and understanding how the magnetic fields influence the detector structure.
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25th International Cryogenic Engineering Conference and the International Cryogenic Materials Conference in 2014, ICEC 25–ICMC 2014