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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.
31

Human Resources Business Partner : Diskrepansen mellan rollens krav och den organisatoriska verkligheten

Möllerström, Jill January 2010 (has links)
No description available.
32

Hormone replacement therapy and effects on mood

Björn, Inger January 2003 (has links)
Background: During the past 5 decades, hormone replacement therapy (HRT) has been used, and appreciated for its beneficial effects, by millions of women in their menopause. As treatment for climacteric symptoms, estrogen is outstanding, and effects on hot flushes, vaginal dryness, and insomnia have been widely documented. The increased risks of venous thrombosis and breast cancer, however, restrict the use of estrogen. Estrogen treatment in women with a remaining uterus includes a progestin, added to protect the endometrium from hyperplasia and malignancies. The long-standing clinical impression, that progestin addition negatively influences mood, has been discussed in previous studies. Mood deterioration is, however, not mortal, although mood is important to the wellbeing and daily functioning of women treated with hormones. Studies of the mental side effects of HRT add to our understanding of steroid effects in the brain. Aims and methods: In our studies, we aimed to establish to what extent negative side effects cause women to discontinue HRT, and find out which drug compounds lead to mood deterioration. The questions asked were whether the type and dose of progestin and the estrogen dose during the progestin addition influence the mood and physical symptoms during sequential HRT. Compliance with HRT and reasons for discontinuing the therapy were evaluated in a retrospective longitudinal follow-up study. Treatment effects were studied in three randomized, double-blind, cross-over trials. During continuous estrogen treatment, effects of sequential addition of a progestin were studied by comparing two different progestins, medroxyprogesterone acetate (MPA) andnorethisterone acetate (NETA), comparing different doses of the same progestin, MPA, and comparing two doses of estrogen during addition of the same dose of MPA. The main outcome measure was the daily rating on mood and physical symptoms kept by the participants throughout the studies. The clinical trials were carried out at three gynecological centers in northern Sweden. Results and conclusions: Besides fear of cancer and a wish to determine whether climacteric symptoms had meanwhile disappeared, negative side effects was the most common reason or discontinuing HRT. Tension in the breasts, weight gain, a depressed mood, abdominal bloating, and irritability were the most important side effects seen both in women who continued HRT and in women who had discontinued the therapy. In our clinical trials, we showed that addition of a progestin to estrogen treatment induces cyclic mood swings characterized by tension, irritability, and depression, as well as increased breast tension, bloatedness, and hot flushes. Women with a history of premenstrual syndrome (PMS) appeared to be more sensitive to the progestin addition and responded with lower mood scores compared with women without previous PMS. In our studies, MPA provoked depressed mood to a lesser extent than did NETA. Surprisingly, the higher dose of MPA (20 mg) enhanced the mood, compared with 10 mg, when added to estrogen treatment. In women continuously treated with 3 mg estradiol, mood and physical symptoms worsened during the progestin addition, as compared with treatment with 2 mg estradiol. The negative side effects seen during sequential HRT have much in common with symptoms seen in the premenstrual dysphoric disorder (PMDD), which is a psychoneuroendocrine disorder with psychiatric expression. Explanations for treatment effects on mood are likely to be found in drug interactions with neurotransmitter systems of the brain. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 2003</p> / digitalisering@umu
33

Women's Health and Drug Utilization

Bardel, Annika January 2007 (has links)
Objectives. To study medication utilization and adherence to prescribed therapy in a female population in central Sweden. To study usage of hormone replacement therapy (HRT) in this population and to assess how HRT users compare to non-users regarding symptom reporting, general health and other variables. To evaluate symptom prevalence adjusted for potential symptom affecting variables. Material and methods. A cross-sectional postal questionnaire study was performed in 1995 in seven counties in central Sweden. A questionnaire was sent to a random sample of 4,200 women aged 35-64, of whom 2,991 responded (71.2%). The questionnaire contained questions on psycho-socio-economic background, quality of life, self-reported health, height and weight, climacteric symptom prevalence, and menopausal status and symptoms. It also comprised questions on medication prescribed during the past year. Results. 40% used prescribed medication and 12% took four drugs or more. Age, educational level, self-rated health, and BMI remained significantly correlated to drug use in multivariate analysis. Adherence ranged from 15%-98% depending on age, a scheduled check-up, perceived importance of medication, concern about medication, taking cardiovascular and respiratory disease drugs. The highest adherence was found for hormonal medication the lowest for musculoskeletal medication. HRT was used by 15% of the women. 13 % used other symptom relieving therapy. HRT users reported higher score of vasomotor symptoms, except for sweating during the daytime. Prevalence of general symptoms did not necessarily increase with age. Especially symptoms related to stress-tension-depression decreased with age. Four different symptom prevalence patterns were found. Conclusions. Age, health status, educational level and body mass index (BMI) appear to affect drug use. Adherence to therapy is highest among elderly women who regard their medication as important and have a scheduled check-up. HRT relieves some vasomotor symptoms but does not affect other symptoms or self-rated health. Prevalence of symptoms related to Stress-tension-depression appears to decrease with age.
34

Degradação de surfactante aniônico em reator UASB com água residuária de lavanderia / Degradation of anionic surfactant in UASB reactor with laundry wastewater

Dagoberto Yukio Okada 25 July 2012 (has links)
Alquilbenzeno linear sulfonado (LAS) é um surfactante presente em água residuária de lavanderia. Em virtude da complexidade de sua degradação, o presente estudo envolveu a análise de alguns fatores, destacando-se: diversidade de co-substratos; tempo de detenção hidráulico (TDH); e concentração de co-substratos. Avaliou-se a degradação de LAS com diferentes co-substratos (metanol, etanol e extrato de levedura) em reator UASB, em TDH de 24 h e 14±2 mg/L de LAS. A influência de TDH e concentração de co-substratos foram analisadas em sete reatores UASB, com 12±3 mg/L de LAS; TDH de 6, 35 e 80 h, e diferentes concentrações de co-substratos (etanol, metanol e extrato de levedura), expressada pela carga orgânica específica (COE), entre 0,03 e 0,18 gDQO/gSTV.d. Ao final, avaliou-se a degradação de LAS em água residuária de lavanderia diluída, nessa mesma configuração de reator com TDH de 35 h e 10±5 mg/L de LAS. Em todos os ensaios foi utilizado inóculo granulado proveniente de reator UASB empregado no tratamento de água residuária de abatedouro de aves, mantendo-se intacta a forma granulada. No ensaio variando co-substratos, observou-se maior remoção de LAS (50%) na presença de co-substrato complexo (extrato de levedura) que na presença de metanol e etanol (29-41%). Diferença pouco significativa entre as comunidades do domínio Archaea e Bacteria (cerca de 60 e 40%, respectivamente) foi observada na presença de diferentes co-substratos, mediante análise de hibridação fluorescente in situ (fluorescent in situ hybridization FISH). Verificou-se maior influência da concentração de co-substratos na degradação de LAS, seguida pelo TDH. Aplicando a menor COE (0,03 gDQO/gSTV.d), obteve-se alta degradação de LAS (76%), enquanto nos reatores variando TDH foram observadas eficiências de 18% (6 h), 37-53% (35 h) e 55% (80 h). Nos reatores variando TDH e concentração de co-substratos, observou-se significativa remoção de LAS no separador de fases (20-53%; na manta de lodo observou-se 13-43%), relacionada à baixa concentração de co-substratos e condição anaeróbia facultativa nessa região. Por meio da técnica de PCR-DGGE (polymerase chain reaction denaturing gradient gel electrophoresis) nas amostras do ensaio variando TDH e concentração de co-substratos, verificou-se maior coeficiente de similaridade na manta de lodo (Archaea: 70-90%; Bacteria: 69-83%), devido à estrutura de grânulo do inóculo utilizado. Verificou-se alta degradação de LAS (82%) no reator com água de lavanderia, atribuída à diversidade de co-substratos (12 ácidos orgânicos voláteis detectados) e à concentração baixa desses co-substratos (COE: 0,03 gDQO/gSTV.d). Mediante análise de pirosequenciamento da região do RNAr 16S de amostras do ensaio com água residuária de lavanderia foram encontrados 147 gêneros, dos quais 32 foram relacionados com a degradação de LAS (gêneros capazes de degradar compostos aromáticos, dessulfonação, e -oxidação). Observou-se significativa abundância relativa (>1%) dos seguintes gêneros relacionados com a degradação de LAS: Comamonas, Dechloromonas, Desulfovibrio, Gemmatimonas, Holophoga, Parvibaculum, Pseudomonas, Rhodanobacter, Sporomusa, Synergistes e Zoogloea. No separador de fases do reator com água de lavanderia, a alta remoção de LAS (90%) e a abundância relativa dos gêneros aeróbios (23%) e anaeróbios (6%) relacionados com a degradação de LAS corroboraram a relação entre remoção de LAS e condição anaeróbia facultativa / Linear alkylbenzene sulfonate (LAS) is a surfactant present in laundry wastewater. Due to the complexity of its degradation, the present study involved the analysis of some features, highlighting: co-substrates diversity; hydraulic retention time (HRT); and co-substrates concentration. The LAS degradation with different co-substrates (methanol, ethanol and yeast extract) was evaluated in UASB reactor, at HRT of 24 h and LAS 14±2 mg/L. The influence of HRT and concentration of co-substrates was analyzed in seven UASB reactors, with LAS 12±3 mg/L; the HRT was 6, 35 and 80 h, and different concentration of co-substrates (methanol, ethanol and yeast extract), as specific organic load rate (SOLR) between 0.03 and 0.18 gCOD/gTVS.d. At the end, the LAS degradation was performed in UASB reactor fed with diluted laundry wastewater, at HRT of 35 h and LAS 10±5 mg/L. In all assays was used a granular inoculum from a UASB reactor employed in treatment of wastewater from poultry slaughterhouse, maintaining the granular form. In the assay varying the co-substrates, it was observed greater LAS removal (50%) in the presence of complex co-substrate (yeast extract) than in the presence of methanol and ethanol (removal: 29-41%). Insignificant difference between the communities from Archaea and Bacteria domain (about 60 and 40%, respectively) was observed in the presence of different co-substrates, according to the fluorescent in situ hybridization (FISH) analysis. It was verified greater influence of cosubstrates concentration than the HRT in the LAS degradation. At the lowest SOLR (0.03 gCOD/gTVS.d), high LAS degradation (76%) was obtained while in the reactors varying the HRT were observed efficiencies of 18% (6 h), 37-53% (35 h) and 55% (80 h). In the reactors varying the HRT and concentration of co-substrates, a significant LAS removal rate (20-53%; in the sludge blanket the rate was 13-43%) was observed in the phase separator, related to the low concentration of co-substrates and the anaerobic facultative condition in this region. By the PCR-DGGE (polymerase chain reaction denaturing gradient gel electrophoresis) technique of samples from the assay varying the HRT and concentration of co-substrates, it was verified great similarity coefficient in the sludge blanket (Archaea: 70-90%; Bacteria: 69- 83%) due to the granule structure of the inoculum used. High LAS degradation (82%) was verified in the reactor with laundry wastewater, which was attributed to the diversity of cosubstrates (12 organic volatile acids detected) and the low concentration of co-substrates (SOLR: 0.03 gCOD/gTVS.d). By pyrosequencing analysis of 16S RNAr genes in the samples from assay with laundry wastewater, it was found 147 genus, which 32 were related to the LAS degradation (genus able to degrade aromatic compounds, desulfonation, and - oxidation). A significant relative abundance (>1%) was observed in the following genus related to the degradation of LAS: Comamonas, Dechloromonas, Desulfovibrio, Gemmatimonas, Holophoga, Parvibaculum, Pseudomonas, Rhodanobacter, Sporomusa, Synergistes and Zoogloea. In the phases separator of the reactor with laundry wastewater, the high LAS removal (90%) and the relative abundance of genus aerobic (23%) and anaerobic (6%) related to the degradation of LAS corroborated the relation between LAS removal and the anaerobic facultative condition
35

Post-Fire Vegetation Recovery Monitoring using MODIS Time Series: A Case Study in California / Övervakning av vegetationsåterhämtning efter brand med hjälp av MODIS-tidsserier: En fallstudie i Kalifornien

Edje, Julia January 2023 (has links)
Human-caused forest fires have increased in magnitude and frequency, affecting global vegetation and requiring a re-evaluation of fire regimes. Changing fire regimes have led to reduced burned areas in fire- dependent ecosystems and increased areas in fire-independent ecosystems, resulting in changes in land cover and posing a threat to native plant communities. This study focuses on monitoring vegetation recovery after fires in California, USA, using the Enhanced Vegetation Index (EVI) from MODIS time series. The goal is to determine the full recovery time and half recovery time (HRT) after forest fires in year 2017 and analyze the influence of burn severity on three land cover classes in two different climate zones in California.Analyzes show that the "Closed Forest" land cover type exhibits the longest recovery period, followed by the "Open Forest" type and “Herbaceous/Shrub” type in both climate zones but no general connection between recovery time and climate zone was observed. It is found that burn severity degree affects HRT but not the full recovery time in both Mediterranean and Semi-arid climate zones. The study mainly highlights the variations in forest fire recovery patterns between land cover types, as well as differences observed between climate zones.
36

Issues in the Development of All-Sputtered ZnO/CdS/CdTe Flexible Solar Cells

Vasko, Anthony C. 25 September 2009 (has links)
No description available.
37

Developing a Mechanistic Understanding and Optimization of the Cannibal Process: Phase II

Easwaran, Sathya Poornima 14 December 2006 (has links)
The Cannibal system, comprised of an activated sludge process integrated with a side stream anaerobic bioreactor, is capable of reducing excess sludge up to 60% compared to the conventional activated sludge process. The hydraulic retention time (HRT) in the Cannibal bioreactor and the interchange rate (the percent of sludge by mass interchanged between the activated sludge system and the bioreactor on daily basis) are the two important operational parameters in the optimization of the Cannibal process. This research was designed to investigate the effect of the Cannibal bioreactor hydraulic retention time and the interchange rate on the solids destruction in the system. The first phase of this study has looked at the effect of three different HRTs, 5 day, 7 day and 10 day. The interchange rate during phase I was 10%. The results showed that the 7 day HRT can be recommended as the minimum retention period for the Cannibal process. The 5 day HRT Cannibal system had some settling problems and high volatile fatty acid content compared to the 7 day HRT Cannibal system. The protein and polysaccharide tests showed that the Cannibal bioreactor is primarily involved in the release of biopolymers which are degraded in the aerobic environment. The second part of this study focused on the effect of the interchange rate (IR) on the solids destruction in the system. The interchange rates that were applied in the system were 15%, 10%, 7%, 5% and 4%.The HRT in the Cannibal bioreactor was 7 day. The results showed that the 10% interchange rate gave maximum solids destruction than the other interchange rates. This implies that 10% is an optimum IR for the Cannibal system. Apart from higher solids wastage, the 4% and 5% IR Cannibal systems had higher volatile fatty acid production. / Master of Science
38

Reator de leito fluidificado em escala aumentada para tratamento de água residuária de lavanderia comercial em co-digestão com esgoto doméstico: otimização das condições operacionais e caracterização taxonômica e funcional dos microrganismos do biofilme / Fluidized bed reactor upscale for treatment of commercial laundry wastewater combined with domestic sewage: optimization of operational conditions and taxonomic and functional characterization of microorganisms in biofilm

Macedo, Thais Zaninetti 25 January 2019 (has links)
O Alquilbenzeno Linear Sulfonado (LAS) é um surfactante aniônico de degradação complexa. Via ensaio cinético em batelada ajustou-se modelo de inibição por excesso de substrato na remoção de LAS e matéria orgânica de água residuária de lavanderia comercial (ARLC) em co-digestão com esgoto doméstico (ED). A adição de 50 mg L-1 de etanol (EOH) resultou em maiores valores para velocidade específica de utilização do substrato (robs) e concentração mais elevada de LAS que fornece o maior robs (18,98 mg LAS L-1 e 2,39 mg LAS L-1 na presença e ausência de etanol, respectivamente). Areia com 1,0 mm de diâmetro foi escolhida como material suporte). Objetivou-se otimizar a remoção do surfactante de ARLC + ED (1:3 volume; &#8764; 20 mg LAS L -1) em RLF em escala aumentada (19,8L) através de: (i) adição de etanol em diferentes dosagens; (ii) variação da velocidade ascensional (vasc) aplicada ao leito; e (iii) aumento do tempo de detenção hidráulica (TDH). Desta forma, para TDH de 18 h foram realizadas as seguintes fases operacionais: (I) ARLC + ED + 1,3 velocidade mínima de fluidificação (vmf); (II) ARLC + ED + 50 mg EOH L -1 + 1,3 vmf; (III) ARLC + ED+200 mg EOH L-1 + 1,3 vmf; (IV) ARLC + ED +200 mg L-1 + 1,0 vmf; (V) ARLC + ED + 200 mg L-1 + 0,7 vmf; (VI) ARLC + ED + 100 mg L-1 + 1,0 vmf; e para TDH de 30 h: (VII) ARLC + ED + 1,0 vmf. Não se observou diferença significativa na eficiência de remoção de DQO e LAS (&#8764; 50%; p < 0,5) nas fases I à IV. O decréscimo da vasc (0,7 vmf) resultou em 29% de eficiência de remoção de LAS (V) e o aumento do TDH em 86% de eficiência de remoção de LAS (VII). Nas fases VI e VII observou-se maior remoção de DQO (&#8805; 70%). As menores vasc e 200 mg EOH L-1 favoreceram acúmulo de ácidos no sistema (IV e V). No efluente do RLF foram identificados 17 compostos recalcitrantes. Para vasc = 0,7 vmf, foi observada maior diversidade de compostos recalcitrantes, em sua maioria, ftalatos. Caracterização taxonômica e funcional dos microrganismos para as fases III, IV e V (variação da vasc) e VII (maior eficiência de remoção de LAS e DQO) foi realizada por metagenômica. Foram identificados microrganismos dos domínios Archaea e Bacteria, sendo que a diminuição da vasc resultou em maior abundância relativa de arqueias metanogênicas, como Methanosarcina e genes relacionados a F420 reducing hydrogenase que é transportadora central de elétrons na metanogênese. Diversidade de gêneros foram identificados do domínio Bacteria (Geobacter, Thauera, Pseudomonas, Chryseobacterium, Sulfuricurvum e Sulfurospirillum, etc.) e genes codificadores de enzimas que atuam nas diferentes etapas de degradação do LAS: (a) adição de fumarato (fumarate redutase); (b) beta-oxidação (3-hidroxiacil-CoA desidrogenase); (c) clivagem do anel benzênico (benzoyl-CoA reductase); (d) dessulfonação (Adenylyl-sulfate reductase). Na amostra da fase VII, foram identificados genes relacionados à etapa de dessulfonação com maior abundância relativa, se comparada às demais fases. Para maior vasc observou-se maior abundância relativa de genes relacionados à fosforilação oxidativa com Chryseobacterium como principal representante. / The linear alkylbenzene sulfonate (LAS) is in the laundry detergent composition and it presents complex degradation. Through kinetics assays in batch tests, an inhibition kinetic model by subtrate excess was adjusted to the data in the removal of LAS and organic matter from laundry wastewater (LW) in co-digestion with domestic sewage (DS). The addition of 50 mg L-1 of ethanol (EOH) to the influent resulted in higher values for the specific substrate rate (robs) as well as higher LAS concentration that provided the maximum LAS utilization rate by the biomass (Sbm) (18.98 mg LAS L-1 and 2. 39 mg LAS L-1 in the presence and absence of ethanol, respectively). Sand with 1.0 mm of diameter was chosen as supporting material for the fluidized bed reactor (FBR). The purpose of the present study was to optimize the removal of surfactant in LW + DS (1: 3 volume; &#8764; 20 mg LAS L-1) by using an upscale FBR (19.8 L) through: (i) adding ethanol in different dosages; (ii) varying the upflow velocity (vup) applied to bed; and (iii) increasing the hydraulic retention time (HRT). Thus, for 18h of HRT, the following stages were performed: (I) LW + DS + 1,3 fluidization minimum velocity (vfm); (II) LW + DS + 50 mg EOH L-1 + 1.3 vfm; (III) LW + DS + 200 mg EOH L-1 + 1.3 vfm; (IV) LW + DS + 200 mg L-1 + 1.0 vfm; (V) LW + DS + 200 mg L-1 + 0.7 vfm; (VI) LW + DW + 100 mg L-1 + 1.0 vfm; and for 30 h of HRT: (VII) LW + DS + 1.0 vfm. There was no significant difference in the efficiency of COD and LAS removal (&#8764; 50%, p < 0.5) in stages I to IV. The vup decrease (0.7 vfm) resulted in LAS removal efficiency of 29% (V) and the HRT increase resulted in LAS removal efficiency of 86% (VII). In stages VI and VII, COD removal &#8805; 70% was observed. Lower vup as well as ethanol dosage of 200 mg L-1 favored system acidification (IV and V). In the FBR effluent, 17 recalcitrant compounds were identified. For vup = 0.7 vfm, large diversity of recalcitrant compounds, mostly phthalates, was observed. A taxonomic and functional characterization of the microorganisms was performed by metagenomics analysis in stages III, IV and V (vup variation) and VII (higher efficiency of LAS and COD removal). Microorganisms of Archaea and Bacteria domains were identified, and the decrease of vup resulted in a higher relative abundance of methanogenic archaea, mainly Methanosarcina. Genes related to F420, which are the central electron carrier in the methanogenesis, were identified. Genera diversity was classified in Bacteria domain (Geobacter, Thauera, Pseudomonas, Pseudomonas, Chryseobacterium, Sulfuricurvum and Sulfurospirillum, etc.). Enzyme-encoding genes that act on different stages of LAS degradation were found: (a) addition of fumarate (fumarate reductase); (b) beta-oxidation (3-hydroxyacyl-CoA dehydrogenase); (c) benzene ring cleavage (benzoyl-CoA reductase) and (d) desulfonation (Adenylyl-sulfate reductase). In stage VII sample, genes related to the desulfonation step were identified with higher relative abundance, when compared to the other stages. For a higher vup, a higher relative abundance of genes related to oxidative phosphorylationwas observed and the genus main representative in that category was Chryseobacterium.
39

Produção de hidrogênio e metabólitos em reator anaeróbio de leito fluidizado e em reator de leito granular expandido a partir de glicerol

Bosio, Morgana 28 March 2014 (has links)
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No. of bitstreams: 1 DissMB.pdf: 3232973 bytes, checksum: 2ca9f79e6634a4d39d6cb45bd3047475 (MD5) Previous issue date: 2014-03-28 / Não recebi financiamento / This work aimed to evaluated the biological hydrogen production using crude glycerol as feedstock in two anaerobic reactors: (1) anaerobic fluidized bed reactor (AFBR), that allows high mass transfer, and (2) an expanded granular sludge blanket reactor, that can used with high efficiency even at high organic loading. In the AFBR, it was evaluated the influence of HRT (14, 12, 10, 8, 6, 4, 2 and 1 hour) in the hydrogen production using crude glycerol as feedstock at 5 g.L-1 and expanded clay as support material. In the EGSB, the HRT varied from 24 to 1 hour, it was used the same feedstock as that used in the AFBR. The reactors were maintained at controlled temperature at 30°C. The noculum for AFBR and EGSB was granular sludge taken from UASB reactor treating poultry slaughterhouse that was previously submitted to heat treatment. In the AFBR, the hydrogen production rate (HPR) increased from 0.08 to 0.73L.h-1.L -1 with the decrease at HRT from 14 to 1 hour, respectively. The hydrogen yield (HY) did not presented the same trend and remained almost unchanged (0.62, 0.76, 0.73, 0.75, 0.60, 0.58, 0.69, 0.85 molH2.mol-1glycerol). For this reactor, the main byproducts were 1,3-propanediol (1,3-PD), ethanol, acetic, butyric and propionic acid. The highest 1,3-PD (1,230 mg.L-1), ethanol (723 mg.L-1), acetic acid (204 mg.L-1), propionic acid (759 mg.L-1) and butyric acid (324 mg.L-1) concentration occurred at HRT of 6, 14, 8, 2, 6 hours, respectively. In the EGSB, the HPR and the HY presented the same trend: HPR increased from 0.018 to 1.708 L.h-1.L-1 and HY increased from 0.19 to 2.87 molH2.mol-1glycerol with the decrease in the HRT from 14 to 1 hour. For both reactors, the AFBR and the EGSB,the highest HPR and HY occurred at HRT of 1 hour. As well as for the AFBR, the main byproducts quantified in the EGSB were 1,3-propanediol (1,3-PD), ethanol, acetic, butyric and propionic acid. The highest 1,3-PD (1,606 mg.L -1), ethanol (400 mg.L-1), acetic acid (219 mg.L-1), propionic acid (1,075 mg.L-1) and butyric acid (248 mg.L-1) concentration occurred at HRT of 16, 12, 16, 8, 20 hours, respectively. / O presente estudo avaliou a produção biológica de hidrogênio utilizando glicerol bruto como matéria-prima em dois reatores anaeróbios: (1) reator anaeróbio de leito fluidizado (RALF), que possibilita elevada transferência de massa, e (2) um reator de leito granular expandido (EGSB), que pode apresentar alta eficiência mesmo quando aplicadas elevadas cargas orgânicas. No RALF, foi avaliada a influência do TDH (14, 12, 10, 8, 6, 4, 2 e 1 hora) na produção de hidrogênio utilizando o glicerol bruto como matéria-prima na concentração de 5 g.L-1 e argila expandida como material de suporte. No EGSB, o TDH estudado variou de 24 a 1 hora, e o substrato e a concentração foram as mesmas que os utilizadas no RALF. Os reatores foram mantidos em temperatura controlada de 30 °C. O inóculo para ambos os reatores, RALF e EGSB, foi lodo granular de reator UASB utilizado no tratamento de água residuária de abatedouro de aves, que foi previamente submetido ao tratamento térmico. No RALF, a taxa de produção de hidrogênio (HPR) aumentou de 0,08 para 0,73L.h-1.L- 1 com a diminuição do TDH de 14 para 1 hora, respectivamente. O rendimento de hidrogênio (HY) não apresentou a mesma tendência e manteve-se praticamente inalterado (0,62; 0,76; 0,73; 0,75; 0,60; 0,58; 0,69 e 0,85 molH2.mol-1glicerol) . Para este reator, os principais metabólitos foram 1,3-propanodiol (1,3-PD), etanol, ácido acético, butírico e propiônico. A maior concentração de 1,3- PD (1.230 mg.l-1), etanol (723 mg.L -1 ), ácido acético (204 mg.L-1), ácido propiônico (759 mg.L-1) e ácido butírico (324 mg.L-1) foi observada nos TDH de 6, 14, 8, 2, 6 horas, respectivamente. No EGSB, o HPR e HY apresentaram a mesma tendência: o HPR aumentou de 0,018-1,708 L.h-1.L-1 e o HY aumentou de 0,19-2,87 molH2.mol-1 glicerol com a diminuição do TDH de 14 para 1 hora. Para ambos os reatores, o RALF e o EGSB, a maior HPR e o maior HY foram observados no TDH de 1 hora. Assim como para o RALF, os principais metabólitos quantificados no EGSB foram 1,3- propanodiol (1,3-PD), etanol, ácido acético, ácido butírico e ácido propiônico. A maior concentração de 1,3- PD (1.606 mg.L-1), etanol (400 mg.L -1), ácido acético (219 mg.L-1), ácido propiônico (1.07 mg.L -1) e ácido butírico (248 mg.L -1) foi observada no TDH de 16, 12, 16, 8 e 20 horas, respectivamente.
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Laser Scanning Confocal Ophthalmoscopy and Polarimetry of Human Immunodeficiency Virus Patients Without Retinopathy, Under Antiretroviral Therapy

Besada, Eulogio, Shechtman, Diana, Black, Greg, Hardigan, Patrick C. 01 March 2007 (has links)
PURPOSE. Confocal laser scanning ophthalmoscopy (HRT; Heidelberg retinal tomograph II) and scanning laser polarimetry (GDx-variable corneal compensator [VCC]) were used to investigate whether early indicators of retinal nerve fiber layer (RNFL) thickness loss could be observed in patients infected with the human immunodeficiency virus (HIV) that had no associated retinopathy or optic neuropathy and were concomitantly receiving antiretroviral medications. METHODS. HRT and GDx-VCC parameters obtained from a group of 13 HIV-positive subjects (n = 26 eyes) on antiretroviral therapy examined with HRT, with a subgroup of six subjects (n = 12 eyes) examined with both HRT and GDx-VCC, were compared with those of a matched HIV-negative control cohort (13 subjects, n = 26 eyes) examined with HRT, with a subgroup of five subjects (n = 10 eyes) examined with both HRT and GDx-VCC. We employed generalized estimating equations for statistical analysis. RESULTS. Reduced mean values for the HRT height variation contour (p < 0.045) and HRT mean RNFL thickness (p < 0.023) were observed in HIV-positive subjects controlling for age, sex, and race. A significantly reduced mean value corresponding to the GDx-VCC superior maximum (p < 0.014) and inferior maximum (p < 0.016) were also observed for the HIV-positive cohort analyzed controlling for age, sex, and race. CONCLUSION. HRT and GDx-VCC indicators of RNFL thickness appear to be significantly reduced in HIV-positive subjects without retinopathy or optic nerve disease using antiretroviral medication, suggesting RNFL loss occurs in this population of HIV-positive patients. The lack of correlation between CD4 counts, viral load, number of antiretroviral medications used, or years from diagnosis of HIV and RNFL thinning, suggests that possibly other factors associated with HIV infection may contribute to the apparent RNFL thickness loss.

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