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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Near-Infrared Spectroscopy neurofeedback (NIRS neurofeedback) em crianças com Transtorno de Déficit de Atenção/Hiperatividade (TDAH)

Londero, Igor January 2015 (has links)
As intervenções com neurofeedback têm tido grande difusão na área como uma alternativa possível para tratamento do Transtorno de Déficit de Atenção/Hiperatividade (TDAH). Este estudo tem o objetivo de avaliar a viabilidade da utilização de um sistema de neurofeedback de baixo custo chamado Near Infrared Spectroscopy/Hemoencephalography Neurofeedback (NIR/HEG-NF) para tratar crianças com TDAH. Método: trata-se de um estudo clínico piloto aberto, que incluiu 5 crianças (3 meninos e 2 meninas - idade 10,4 ± 0,89 anos) com TDAH-C (tipo combinado). Os indivíduos completaram um programa de 24 sessões de NIR/HEG-NF, duas ou três vezes por semana. Os seguintes desfechos foram avaliados pré e pós-tratamento: 1) sintomas de desatenção e hiperatividade; 2) desempenho neuropsicológico; 3) imagens de SPECT cerebral; 4) qualidade de vida; e 5) efeitos adversos. Resultados: houve maior resistência do que o esperado para a participação dos indivíduos devido a vários fatores, tais como logísticos para a participação nas sessões e requerimento de não uso de medicação durante o protocolo. Detectamos uma diferença significativa na comparação pré e pós-intervenção nos escores atribuídos pelos pais na dimensão de hiperatividade e impulsividade do Swanson, Nolan and Pelham Questionnaire (SNAP-IV) (p = .042; tamanho de efeito [ES] =.38) e uma tendência de melhora nos escores atribuídos pelos pais e professores na dimensão desatenção (p = .066; ES = .47 / p = .068; ES = .60) naquelas crianças que finalizaram o tratamento. Detectamos uma tendência de aumento perfusional em diferentes partes do córtex cerebral em três indivíduos. As comparações pré e pós-intervenção nas outras medidas não indicaram diferenças estatisticamente significativas. Não foram relatados efeitos adversos significativos. Discussão: Os achados iniciais sugerem que o NIR/HEG-NF como tratamento para sintomas de TDAH pode ser promissor e deve ser melhor investigado. O protocolo lança luz sobre novas abordagens para avaliar a eficácia da intervenção. Pode-se, por exemplo, implementar o programa de intervenção no ambiente escolar e com uso concomitante de medicamentos para superar as resistências na alocação de pacientes e para uma avaliação com maior validade externa. / Background and objectives: Neurofeedback interventions have been quick and extensively introduced for clinicians to treat Attention-Deficit/Hyperactivity Disorder (ADHD). This study aims to assess the feasibility of using a low cost neurofeedback system called Near Infrared Spectroscopy/ Hemoencephalography Neurofeedback (NIR/HEG-NF) for treating children with ADHD. Method: This open pilot clinical study included 5 children (3 boys and 2 girls - age 10.4 ± 0.89 years) with ADHD-C (combined type). The subjects completed a program of 24 sessions of NIR/HEG-NF, two or three times a week. The following outcomes were assessed pre and post-treatment: 1) clinical symptoms of inattention and hyperactivity; 2) neuropsychological performance; 3) brain SPECT images; 4) quality of life and; 5) adverse effects. Results: Higher resistance than expected was experienced for patient allocation due to logistic reasons to attend the sessions in the hospital and the requirement of not using medication during the protocol. We detected a significant decrease in hyperactivity/impulsivity comparing pre and post-intervention scores in the parent’s Swanson, Nolan and Pelham Questionnaire - SNAP-IV (p = .042; Effect Size [ES] r = .38) and a trend of improvement in scores attributed by parents and teachers in inattention (p = .066; r = .47 / p = .068; r = .68) . We detected a trend for increased perfusion in different parts of the entire cortex in 3 subjects. Comparisons between pre and post-intervention scores in other measures did not suggest meaningful differences. No significant adverse effects were reported. Discussion: Our initial findings suggest that NIR/HEG-NF technique might be promising and should be further investigated. The protocol shed light on new approaches to assess the effectiveness of the intervention such as the need to both implement the intervention program in a school environment and to pursue the investigation of the treatment effects with concomitant use of medications to surpass resistances to enroll patients and to have an assessment with more external validity.
42

Monitoring of cerebral oxygenation, cerebrovascular reactivity and circulatory function in preterm infants

Sortica da Costa, Cristine January 2018 (has links)
Monitoring of cerebral oxygenation, cerebrovascular reactivity and circulatory function in preterm infants Brain injury in the preterm infant is associated with death and lifelong disability. Cerebral hypoxia and fluctuations in cerebral blood flow in the first two days of life have been implicated in the pathophysiology of haemorrhagic and ischaemic brain injury. Monitoring of haemodynamic changes during the early transitional circulation from in-utero to ex-utero life are currently based on standard measurements of systemic oxygenation and mean arterial blood pressure, with no reliable assessment of end-organ perfusion. In this thesis, measurements using near-infrared spectroscopy (NIRS) and functional echocardiography were made to assess cerebral perfusion and systemic blood flow in a cohort of preterm infants undergoing intensive care. This thesis is divided into four sections: i) The feasibility of continuous monitoring of cerebral oxygenation and cerebrovascular reactivity is demonstrated in a series of case reviews, and the association between cerebral oxygenation and cerebrovascular reactivity with outcome of brain injury and mortality is described. ii) Combining measurements of systemic blood flow with end organ perfusion was applied to define MABPOPT in preterm infants based on an index of cerebrovascular reactivity. Deviations below MABPOPT were associated with intraventricular haemorrhage and mortality. iii) The complexity of brain and systemic signals was studied by using multi-scale entropy analysis. Most studies using cerebral NIRS or systemic measurements of blood flow use linear analysis; however, a complex biological system, such as the human brain, includes many regulatory mechanisms that interact in a complex manner, resulting in effects that cannot be understood wholly through the analysis of its individual constituents. Lower complexity of brain signals was observed in infants who developed intraventricular hemorrhage or died. iv) Changes in systemic and cerebral oxygenation in a cohort of preterm infants in the first 48 hours of life was assessed using functional echocardiography. The patterns of changes in cardiac output and cerebral oxygenation in infants who did and did not have intraventricular haemorrhage are discussed. Furthermore, the relationship between the presence of a haemodynamically significant ductus arteriosus and brain injury is assessed.
43

Genetic Analysis of Bread Making Quality Stability in Wheat using a Halberd X Len Recombinant Inbred Line Population

Poudel, Ashima 2012 May 1900 (has links)
Wheat grain quality has a complex genetic architecture heavily influenced by the growing environment. Consistency in wheat quality not only affects the efficiency of milling and baking but also the quality of end-use products. The objectives of this study were to 1) analyze the different wheat quality parameters in Recombinant Inbred Lines (RILs) grown under different environments, and 2) to identify Quantitative Trait Loci (QTLs) associated with quality stability in RILs grown under different environments. A set of 180 RILs derived from two spring wheat lines 'Halberd' and 'Len' were grown at Uvalde and College Station TX, in the 2009/2010 growing season and at Chillicothe and College Station TX, in 2010/2011 growing seasons. The experiment was laid out in Randomized Complete Block Design (RCBD) with four replications within each location. Each line was tested for multiple quality traits that included grain hardness, protein content, dough mixing properties and bread baking quality using Single Kernel Characterization System (SKCS), Near-Infrared Reflectance Spectrometry (NIRS) analysis, mixograph and the Sodium Dodecyl Sulfate Sedimentation (SDSS) test. Genetic linkage map construction was carried out with 116 single nucleotide polymorphism (SNP) markers in the RILs. Then composite interval mapping was carried out to identify QTLs associated with quality traits. The SDSS column height was positively correlated across four environments. Similarly, it was found to have significant positive correlation with mixing tolerance and peak time within and also across locations. However, the SDSS was negatively correlated with the hardness index. The protein percent was not significant with any of the quality traits within and across environments. We were able to detect many QTLs for different quality traits but most of them were site specific. Only a few QTLs were consistent across environments. Most of the QTLs for quality traits i.e., SDSS, peak time, mixing tolerance and hardness index were identified on chromosome 1B. We were able to detect overlapped QTLs for SDSS column height and mixing tolerance on chromosome 1B. Furthermore, overlapping QTLs for mixing tolerance and peak time were detected on an unknown chromosome. We also detected overlapping QTLs for hardness index on chromosome 1B. We identified one stable QTL for SDSS column height on chromosome 4B. This QTL was detected based on the coefficient of variation (CV) for SDSS in four different environments.
44

Variation of eubacterial and denitrifying bacterial biofilm communities among constructed wetlands

Milenkovski, Susann, Thiere, Geraldine, Weisner, Stefan, Berglund, Olof, Lindgren, Per-Eric Unknown Date (has links)
Bacteria play important roles in the transformation of nutrients in wetlands, but few studies have examined parameters affecting variation in bacterial community composition between wetlands. We compared the composition of eubacterial and denitrifying bacterial biofilm communities in 32 agricultural constructed wetlands in southern Sweden, and the extent to which wetland environmental parameters could explain the observed variation. Structure and richness of the eubacterial 16S rRNA gene and three denitrifying bacterial enzyme genes (nirK, nirS and nosZ), analysed by molecular fingerprinting methods, varied among the constructed wetlands, which could be partly explained by different environmental parameters. Results from the enzyme gene analyses were also compared to determine whether the practice of using a single denitrifying bacterial gene could characterize the overall community composition of denitrifying bacteria. We found that nirK was more diverse than both nirS and the nosZ, and the band structure and richness of the three genes were not related to the sam environmental parameters. This suggests that using a single enzyme gene may not suffice to characterize the community composition of denitrifying bacteria in constructed agricultural wetlands. / <p>Included in doctoral thesis: Milenkovski, Susann. Structure and Function of Microbial Communities in Constructed Wetlands - Influence of environmental parameters and pesticides on denitrifying bacteria. Lund University 2009.</p>
45

Impact of undesirable plant communities on the carrying capacity and livestock performance in pastoral systems of south-western Uganda

Byenkya, Gilbert Steven 30 September 2004 (has links)
The impact of undesirable plant communities (Cymbopogon afronardus and woody species dominated by Acacia species) on livestock carrying capacity and performance was investigated on 15 farms in an Acacia/Cymbopogon dominated pastoral system of south-western Uganda. Species prevalence based on basal cover for grasses, frequency for forbs and effective canopy cover for trees/shrubs were determined on farms. The PHYGROW model was used to predict forage productivity for computation of carrying capacity. The NIRS/NUTBAL nutritional management system was used to determine cattle dietary CP and DOM through fecal scans and to estimate animal performance. Cymbopogon afronardus had a prevalence of 10.29% among the grasses while Acacia gerrardii (34.37%) and Acacia hockii (33.66%) were the most prevalent woody species. Forage productivity differed significantly among the farms with a mean long-term annual forage yield of 4560(SE+41) kg/ha. Farms infested with Cymbopogon and woody species produced the least amount of forage and therefore had the lowest carrying capacities (0.38 -0.39 AU/ha) while improved farms had comparatively higher forage yields with higher carrying capacities (0.49 - 0.52 AU/ha). A mean carrying capacity for the system was estimated at 0.44 AU/ha using a 25% harvest efficiency for ANPP. All the farms were overstocked, on average by 3.2 times. Livestock BCS, diet CP and DOM were significantly different (P<0.0001) among the different farm types. BCS were highest on improved farms and lowest on Cymbopogon infested farms while dietary CP and DOM values were lowest on improved farms and highest on farms with a high woody component. Farms with a relatively high woody component exhibited intermediate BCS despite the high dietary CP values. Cattle on Cymbopogon infested farms had consistently lower body weights over the months although there were no significant differences in daily live weight gains among farms. Recommendations included need for research into appropriate control measures for both Cymbopogon afronardus and woody species, farmer sensitization about overstocking, research to improve forage quality on improved farms and need for feed supplementation for improved breeds on improved farms. Integration of NIRS/NUTBAL and PHYGROW models into the research and management systems was desirable. The observed increase in Sporobolus spp. required investigation.
46

Les adaptations du rachis lombaire en situation aiguës et chroniques / Low back adaptations in acute and chronic situations

Dupeyron, Arnaud 15 September 2010 (has links)
Le rachis lombaire est à la fois capable de répondre à des exigences de stabilité pour protéger les structures neurologiques ou ostéo-ligamentaires et de mouvement pour assumer les gestes de la vie quotidienne, professionnelle et sportive. La lombalgie, pathologie multifactorielle, s'accompagne de perturbations musculaires, réflexes ou comportementales. La complexité de ces adaptations explique pourquoi il est encore difficile de savoir comment un sujet devient lombalgique ou pourquoi il le reste. Ce travail de recherche s'est focalisé sur l'étude de certaines adaptations du rachis lombaire en situation aiguës ou chroniques. Les objectifs étaient d'analyser l'influence (i) des tissus de soutien sur le comportement musculaire lombaire (ii) du gainage abdominal sur l'efficience des membres inférieurs, (iii) de la fatigue des érecteurs spinaux sur la réponse réflexe chez le sujet sain et (iv) d'un programme de rééducation chez le lombalgique. Les résultats obtenus soulignent le rôle central de l'effecteur neuromusculaire lombaire. Le maintien de certaines postures entraîne des adaptations mécaniques (pression intramusculaire) et métaboliques (oxygénation musculaire) limitant l'efficience des érecteurs spinaux. Le renforcement abdominal, probablement par son action stabilisatrice lombaire, modifie la raideur du système tronc -membres inférieurs et peut-être l'aptitude au saut vertical. Une fatigue lombaire induite provoque une adaptation réflexe chez le sujet sain (gain d'amplitude et peut-être de latence) pour compenser la perte de force. Enfin, un programme de restauration fonctionnelle permettrait, chez le lombalgique chronique, de modifier les capacités d'anticipation en limitant les activations musculaires exagérées et la réponse réflexe à une perturbation, évoquant l'émergence de nouvelles stratégies d'adaptation. Ce travail suggère la possibilité de nouvelles approches dans un cadre sportif ou médical. / The lumbar spine is able to meet both stability requirements for protecting neurological and osteoligamentous spine structures and movement requirements for performing professional, sports, and daily life activities. Low back pain, a multi-factorial disease, is associated with abnormal muscle function, neuromuscular alterations, and adverse behavioural reactions. The complexity and the variability of all these changes explain why the exact cause of back pain remains unknown. This thesis focused on the study of the lumbar spine adaptations in various acute or chronic situations. The goal was to explore (i) the influence of posture and passive contributions on paraspinal muscle pressure and oxygenation adaptations, (ii) the consequences of abdominal reinforcement on trunk and leg stiffness, (iii) the effects of induced paraspinal fatigue or (iv) rehabilitation programs on reflex modulation in healthy subjects and chronic low back pain patients, respectively. The results emphasize the central role of the neuromuscular lumbar effector. Maintaining certain postures causes mechanical and oxygenation paraspinal muscular changes that may explain passive limitations on paraspinal muscle efficiency; the modifications induced by abdominal training in healthy subjects suggest a possible role of the spine on trunk and leg stiffness changes; a paraspinal muscle fatigue paradigm illustrates the reflex modulation which compensates a loss of force; finally, a functional restoration program designed for chronic low back pain disorders targets neuromuscular behaviour changes via modulation of the trunk reflex response, thus advocating a possible way to increase the range of control strategies. This work opens the door for new therapeutic strategies.
47

Near-Infrared Spectroscopy neurofeedback (NIRS neurofeedback) em crianças com Transtorno de Déficit de Atenção/Hiperatividade (TDAH)

Londero, Igor January 2015 (has links)
As intervenções com neurofeedback têm tido grande difusão na área como uma alternativa possível para tratamento do Transtorno de Déficit de Atenção/Hiperatividade (TDAH). Este estudo tem o objetivo de avaliar a viabilidade da utilização de um sistema de neurofeedback de baixo custo chamado Near Infrared Spectroscopy/Hemoencephalography Neurofeedback (NIR/HEG-NF) para tratar crianças com TDAH. Método: trata-se de um estudo clínico piloto aberto, que incluiu 5 crianças (3 meninos e 2 meninas - idade 10,4 ± 0,89 anos) com TDAH-C (tipo combinado). Os indivíduos completaram um programa de 24 sessões de NIR/HEG-NF, duas ou três vezes por semana. Os seguintes desfechos foram avaliados pré e pós-tratamento: 1) sintomas de desatenção e hiperatividade; 2) desempenho neuropsicológico; 3) imagens de SPECT cerebral; 4) qualidade de vida; e 5) efeitos adversos. Resultados: houve maior resistência do que o esperado para a participação dos indivíduos devido a vários fatores, tais como logísticos para a participação nas sessões e requerimento de não uso de medicação durante o protocolo. Detectamos uma diferença significativa na comparação pré e pós-intervenção nos escores atribuídos pelos pais na dimensão de hiperatividade e impulsividade do Swanson, Nolan and Pelham Questionnaire (SNAP-IV) (p = .042; tamanho de efeito [ES] =.38) e uma tendência de melhora nos escores atribuídos pelos pais e professores na dimensão desatenção (p = .066; ES = .47 / p = .068; ES = .60) naquelas crianças que finalizaram o tratamento. Detectamos uma tendência de aumento perfusional em diferentes partes do córtex cerebral em três indivíduos. As comparações pré e pós-intervenção nas outras medidas não indicaram diferenças estatisticamente significativas. Não foram relatados efeitos adversos significativos. Discussão: Os achados iniciais sugerem que o NIR/HEG-NF como tratamento para sintomas de TDAH pode ser promissor e deve ser melhor investigado. O protocolo lança luz sobre novas abordagens para avaliar a eficácia da intervenção. Pode-se, por exemplo, implementar o programa de intervenção no ambiente escolar e com uso concomitante de medicamentos para superar as resistências na alocação de pacientes e para uma avaliação com maior validade externa. / Background and objectives: Neurofeedback interventions have been quick and extensively introduced for clinicians to treat Attention-Deficit/Hyperactivity Disorder (ADHD). This study aims to assess the feasibility of using a low cost neurofeedback system called Near Infrared Spectroscopy/ Hemoencephalography Neurofeedback (NIR/HEG-NF) for treating children with ADHD. Method: This open pilot clinical study included 5 children (3 boys and 2 girls - age 10.4 ± 0.89 years) with ADHD-C (combined type). The subjects completed a program of 24 sessions of NIR/HEG-NF, two or three times a week. The following outcomes were assessed pre and post-treatment: 1) clinical symptoms of inattention and hyperactivity; 2) neuropsychological performance; 3) brain SPECT images; 4) quality of life and; 5) adverse effects. Results: Higher resistance than expected was experienced for patient allocation due to logistic reasons to attend the sessions in the hospital and the requirement of not using medication during the protocol. We detected a significant decrease in hyperactivity/impulsivity comparing pre and post-intervention scores in the parent’s Swanson, Nolan and Pelham Questionnaire - SNAP-IV (p = .042; Effect Size [ES] r = .38) and a trend of improvement in scores attributed by parents and teachers in inattention (p = .066; r = .47 / p = .068; r = .68) . We detected a trend for increased perfusion in different parts of the entire cortex in 3 subjects. Comparisons between pre and post-intervention scores in other measures did not suggest meaningful differences. No significant adverse effects were reported. Discussion: Our initial findings suggest that NIR/HEG-NF technique might be promising and should be further investigated. The protocol shed light on new approaches to assess the effectiveness of the intervention such as the need to both implement the intervention program in a school environment and to pursue the investigation of the treatment effects with concomitant use of medications to surpass resistances to enroll patients and to have an assessment with more external validity.
48

Monitoramento em tempo real da hidr?lise enzim?tica do baga?o da casca de coco verde por espectroscopia no infravermelho pr?ximo (NIRS) / Real time monitoring of enzymatic hydrolysis of coconut husk by near-infrared spectroscopy (NIRS)

Nascimento, Ruthin?ia J?ssica Alves do 29 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-10T12:38:21Z No. of bitstreams: 1 RuthineiaJessicaAlvesDoNascimento_TESE.pdf: 6329302 bytes, checksum: f22f9fe27a39b94fcd9cc9ae37adb3f4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-11T13:40:12Z (GMT) No. of bitstreams: 1 RuthineiaJessicaAlvesDoNascimento_TESE.pdf: 6329302 bytes, checksum: f22f9fe27a39b94fcd9cc9ae37adb3f4 (MD5) / Made available in DSpace on 2017-01-11T13:40:12Z (GMT). No. of bitstreams: 1 RuthineiaJessicaAlvesDoNascimento_TESE.pdf: 6329302 bytes, checksum: f22f9fe27a39b94fcd9cc9ae37adb3f4 (MD5) Previous issue date: 2016-06-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Este trabalho, em uma primeira etapa, investiga a aplica??o da espectroscopia no infravermelho pr?ximo para a caracteriza??o qualitativa r?pida da fibra da casca de coco verde e avalia o potencial deste material lignocelul?sico para a produ??o de etanol de segunda gera??o. Em uma segunda etapa, os dados de espectroscopia no infravermelho pr?ximo foram associados a m?todos de pr?-tratamento matem?tico de dados diferentes. M?todos de calibra??o multivariada foram investigados quanto ao seu potencial para o monitoramento em tempo real do processo de hidr?lise enzim?tica da fibra da casca de coco verde. A fibra da casca de coco verde foi submetida a quatro tipos de pr?-tratamentos f?sico-qu?micos: Pr?-tratamento com ?cido sulf?rico dilu?do (2% p/v), pr?-tratamento com ?cido fosf?rico dilu?do (0,2% p/v), pr?-tratamento alcalino (NaOH 0,5% p/v) e pr?-tratamento hidrot?rmico. Foram avaliadas as mudan?as de morfologia, composi??o qu?mica e de ?ndice de cristalinidade ocasionadas pelos pr?-tratamentos f?sico-qu?micos utilizados. Tamb?m foram investigadas a influ?ncia dos pr?-tratamentos nos rendimentos da hidr?lise enzim?tica e no rendimento de etanol te?rico deste processo. Mudan?as nos teores de lignina, hemicelulose e celulose cristalina foram caracterizadas por m?todos tradicionais, como MEV, DRX e utilizando um m?todo anal?tico alternativo, a espectroscopia NIR, onde bons resultados foram obtidos. O pr?-tratamento com ?cido fosf?rico dilu?do mostrou-se como o mais eficiente quando se visa ? produ??o de bioetanol, resultando em 39,16% de rendimento de hidr?lise enzim?tica e 83,68 L/t de fibra de rendimento de etanol te?rico. Os modelos de calibra??o para o monitoramento foram constru?dos e otimizados pelo processo de valida??o cruzada e a capacidade preditiva destes foram analisadas pelo processo de valida??o externa. Os pr?-tratamento matem?ticos realizados nos dados espectrais foram a varia??o padr?o normal (Standard normal variate-SNV), corre??o multiplicativa de luz (Multiplicative scatter correction-MSC) e suaviza??o por media m?vel (Smoothing moving average-SMA) associados a 1? e 2? derivada de Savitzky-Golay. Os intervalos de calibra??o para ART, glicose, convers?o de celulose e rendimento de etanol te?rico foram: 0,12 ? 7,87 g.L-1; 0,00 ? 5,87 g.L-1; 0,00 ? 28,85% e 0,00 ? 61,68 L/t de fibra. Os melhores modelos de calibra??o para quantifica??o de ART, glicose, convers?o de celulose e rendimento de etanol te?rico foram obtidos para o pr?-tratamento matem?tico SMA + 2? derivada apresentando valores de R2 e RMSEP iguais a, 0,98 e 0,1994 g.L-1, para ART; 0,99 e 0,0266g.L-1, para glicose; 0,99 e 0,1839%, para convers?o de celulose; 0,99 e 0,2279 L/t para rendimento de etanol te?rico. Os modelos de calibra??o obtidos foram utilizados para o monitoramento de um processo de hidr?lise enzim?tica da fibra da casca de coco verde com a obten??o de resultados satisfat?rios para o monitoramento da etapa de hidr?lise enzim?tica do processo de fabrica??o de etanol de segunda gera??o. / This study investigates the application of near infrared spectroscopy for rapid qualitative characterization of coconut husk fiber and evaluates the potential of this lignocellulosic material for producing second-generation ethanol. The near infrared spectroscopy associated with methods of data mathematical pretreatment and multivariate calibration methods have been used to their potential for real time monitoring of coconut husk fiber enzymatic hydrolysis process. The coconut husk was subjected to four types of physico-chemical pretreatments: Pretreatment with dilute sulfuric acid (2% w/v), pretreatment with dilute phosphoric acid (0.2% w/v), alkaline pretreatment (NaOH 0.5% w/v) and hydrothermal pretreatment. Morphological changes, chemical composition and crystallinity index variations caused by the physical-chemical pretreatments were evaluated. Also, the influence of pretreatments in enzymatic hydrolysis yield and the theoretical ethanol yield was investigated. The changes in lignin, hemicellulose and crystalline cellulose were characterized by traditional methods such as SEM and XRD as well as using an alternative analytical method such as NIR spectroscopy showing good results. Pretreatment with dilute phosphoric acid proved to be more efficient aiming the production of bioethanol, resulting in aproximately 39.16% of enzymatic hydrolysis yield and 83.68 L/t of theoretical ethanol yield. The monitoring calibration models were built and optimized with the cross-validation process and the models predictive ability were analyzed by the external validation. The mathematical pretreatments performed on spectral data were Standard normal variation (SNV), Multiplicative scatter correction (MSC) and Smoothing moving average (SMA) coupled with 1st and 2nd derivative of Savitzky-Golay. The calibration intervals for ART, glucose, cellulose conversion and theoretical ethanol yield were: 0.12 ? 7.87 g.L-1; 0.00 ? 5.87 g.L-1; 0.00 ? 28.85% and 0,00 ? 61,68 L/t of fiber. The best calibration models for quantification of ART, glucose, cellulose conversion and the theoretical ethanol yield were obtained for the mathematical pretreatment SMA + 2nd derivative having R2 and RMSEP values equal to, 0.98 and 0.1994 g.L-1, for ART; 0.99 and 0,0266 g.L-1 for glucose; 0.99 and 0.1839% for cellulose conversion; 0.99 and 0.2279 L/t of theoretical ethanol yield. The obtained calibration models were used for monitoring an enzymatic hydrolysis process of coconut husk with satisfactory results.
49

Near-Infrared Spectroscopy neurofeedback (NIRS neurofeedback) em crianças com Transtorno de Déficit de Atenção/Hiperatividade (TDAH)

Londero, Igor January 2015 (has links)
As intervenções com neurofeedback têm tido grande difusão na área como uma alternativa possível para tratamento do Transtorno de Déficit de Atenção/Hiperatividade (TDAH). Este estudo tem o objetivo de avaliar a viabilidade da utilização de um sistema de neurofeedback de baixo custo chamado Near Infrared Spectroscopy/Hemoencephalography Neurofeedback (NIR/HEG-NF) para tratar crianças com TDAH. Método: trata-se de um estudo clínico piloto aberto, que incluiu 5 crianças (3 meninos e 2 meninas - idade 10,4 ± 0,89 anos) com TDAH-C (tipo combinado). Os indivíduos completaram um programa de 24 sessões de NIR/HEG-NF, duas ou três vezes por semana. Os seguintes desfechos foram avaliados pré e pós-tratamento: 1) sintomas de desatenção e hiperatividade; 2) desempenho neuropsicológico; 3) imagens de SPECT cerebral; 4) qualidade de vida; e 5) efeitos adversos. Resultados: houve maior resistência do que o esperado para a participação dos indivíduos devido a vários fatores, tais como logísticos para a participação nas sessões e requerimento de não uso de medicação durante o protocolo. Detectamos uma diferença significativa na comparação pré e pós-intervenção nos escores atribuídos pelos pais na dimensão de hiperatividade e impulsividade do Swanson, Nolan and Pelham Questionnaire (SNAP-IV) (p = .042; tamanho de efeito [ES] =.38) e uma tendência de melhora nos escores atribuídos pelos pais e professores na dimensão desatenção (p = .066; ES = .47 / p = .068; ES = .60) naquelas crianças que finalizaram o tratamento. Detectamos uma tendência de aumento perfusional em diferentes partes do córtex cerebral em três indivíduos. As comparações pré e pós-intervenção nas outras medidas não indicaram diferenças estatisticamente significativas. Não foram relatados efeitos adversos significativos. Discussão: Os achados iniciais sugerem que o NIR/HEG-NF como tratamento para sintomas de TDAH pode ser promissor e deve ser melhor investigado. O protocolo lança luz sobre novas abordagens para avaliar a eficácia da intervenção. Pode-se, por exemplo, implementar o programa de intervenção no ambiente escolar e com uso concomitante de medicamentos para superar as resistências na alocação de pacientes e para uma avaliação com maior validade externa. / Background and objectives: Neurofeedback interventions have been quick and extensively introduced for clinicians to treat Attention-Deficit/Hyperactivity Disorder (ADHD). This study aims to assess the feasibility of using a low cost neurofeedback system called Near Infrared Spectroscopy/ Hemoencephalography Neurofeedback (NIR/HEG-NF) for treating children with ADHD. Method: This open pilot clinical study included 5 children (3 boys and 2 girls - age 10.4 ± 0.89 years) with ADHD-C (combined type). The subjects completed a program of 24 sessions of NIR/HEG-NF, two or three times a week. The following outcomes were assessed pre and post-treatment: 1) clinical symptoms of inattention and hyperactivity; 2) neuropsychological performance; 3) brain SPECT images; 4) quality of life and; 5) adverse effects. Results: Higher resistance than expected was experienced for patient allocation due to logistic reasons to attend the sessions in the hospital and the requirement of not using medication during the protocol. We detected a significant decrease in hyperactivity/impulsivity comparing pre and post-intervention scores in the parent’s Swanson, Nolan and Pelham Questionnaire - SNAP-IV (p = .042; Effect Size [ES] r = .38) and a trend of improvement in scores attributed by parents and teachers in inattention (p = .066; r = .47 / p = .068; r = .68) . We detected a trend for increased perfusion in different parts of the entire cortex in 3 subjects. Comparisons between pre and post-intervention scores in other measures did not suggest meaningful differences. No significant adverse effects were reported. Discussion: Our initial findings suggest that NIR/HEG-NF technique might be promising and should be further investigated. The protocol shed light on new approaches to assess the effectiveness of the intervention such as the need to both implement the intervention program in a school environment and to pursue the investigation of the treatment effects with concomitant use of medications to surpass resistances to enroll patients and to have an assessment with more external validity.
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Near-Infrared Spectral Measurements and Multivariate Analysis for Predicting Glass Contamination of Boiler Fuel

Winn, Olivia, Thekkemadathil Sivaram, Kiran January 2017 (has links)
This degree project investigates how glass contamination in refuse-derived fuel for a fluidised bed boiler can be detected using near-infrared spectroscopy. It is motivated by the potential to reduce greenhouse gas emissions by replacing fossil fuels with refuse-derived fuel. The intent was to develop a multivariate predictive model of near-infrared spectral data to detect the presence of glass cullet against a background material that represents refuse-derived fuel. Existing literature was reviewed to confirm the usage of near-infrared spectroscopy as a sensing technology and determine the necessity of glass detection. Four unique background materials were chosen to represent the main components in municipal solid waste: wood shavings, shredded coconut, dry rice and whey powder. Samples of glass mixed with the background material were imaged using near-infrared spectroscopy, the resulting data was pre-processed and analysed using partial least squares regression. It was shown that a predictive model for quantifying coloured glass cullet content in one of several background materials were reasonably accurate with a validation coefficient of determination of 0.81 between the predicted and reference data. Models that used data from a single type of background material, wood shavings, were more accurate. Models for quantifying clear glass cullet content were significantly less accurate. These types of models could be applied to predict coloured glass content in different kinds of background materials. However, the presence of clear glass in municipal solid waste, and thus refuse-derived fuel, limit the opportunities to apply these methods to the detection of glass contamination in fuel.

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