943 resultados para Ópio


Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper reports experiments on the use of a recently introduced advection bounded upwinding scheme, namely TOPUS (Computers & Fluids 57 (2012) 208-224), for flows of practical interest. The numerical results are compared against analytical, numerical and experimental data and show good agreement with them. It is concluded that the TOPUS scheme is a competent, powerful and generic scheme for complex flow phenomena.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Abstract Background Invasive cervical cancer is the second most common malignant tumor affecting Brazilian women. Knowledge on Human Papillomavirus (HPV) genotypes in invasive cervical cancer cases is crucial to guide the introduction and further evaluate the impact of new preventive strategies based on HPV. We aimed to provide updated comprehensive data about the HPV types’ distribution in patients with invasive cervical cancer. Methods Fresh tumor tissue samples of histologically confirmed invasive cervical cancer were collected from 175 women attending two cancer reference hospitals from São Paulo State: ICESP and Hospital de Câncer de Barretos. HPV detection and genotyping were performed by the Linear Array HPV Genotyping Test (Roche Molecular Diagnostics, Pleasanton,USA). Results 170 out of 172 valid samples (99%) were HPV DNA positive. The most frequent types were HPV16 (77.6%), HPV18 (12.3%), HPV31 (8.8%), HPV33 (7.1%) and HPV35 (5.9%). Most infections (75%) were caused by individual HPV types. Women with adenocarcinoma were not younger than those with squamous cell carcinoma, as well, as women infected with HPV33 were older than those infected by other HPV types. Some differences between results obtained in the two hospitals were observed: higher overall prevalence of HPV16, absence of single infection by HPV31 and HPV45 was verified in HC-Barretos in comparison to ICESP patients. Conclusions To our knowledge, this is one of the largest studies made with fresh tumor tissues of invasive cervical cancer cases in Brazil. This study depicted a distinct HPV genotype distribution between two centers that may reflect the local epidemiology of HPV transmission among these populations. Due to the impact of these findings on cervical cancer preventive strategies, extension of this investigation to routine screening populations is warranted.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Microalgae are a promising source of raw material for biodiesel production. This review discusses the latest developments related to the application of microalgae biomass for biodiesel production. Characterization of fatty acid of microalgae and comparisons with other sources of raw materials and processes are presented. Furthermore, technological perspectives and approaches for growing microalgae in photobioreactors, microalgal oil extraction techniques, and procedures for synthesizing biodiesel are reviewed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Gracilaria domingensis (Kützing) Sonder ex Dickie and Gracilaria birdiae (Plastino & Oliveira) (Gracilariales, Rhodophyta) are seaweeds that occur on the Brazilian coast. Based on their economic and pharmaceutical importance, we investigated the antioxidant activity of the methanolic, ethyl acetate and hexane extracts of both species. The hexane extracts display a high antioxidant activity and comparative analyses indicated G. birdiae as the most active species. Chemical investigation of these fractions showed several carotenoids and fatty acids, as well as cholesterol and sitosterol derivatives. HPLC-DAD analysis of G. birdiae showed violaxanthin (0.04 μg.mg-1 of dry material), antheraxanthin (5.31 μg.mg-1), aloxanthin (0.09 μg.mg-1), zeaxanthin (0.45 μg.mg-1) and β-carotene (0.37 μg.mg-1) as the major carotenoids. G. domingensis showed a similar carotenoid profile, however, with much lower concentration than G. birdiae. Gas chromatography coupled to mass spectrometry was used to determine other nonpolar compounds of these seaweeds. The main compounds detected in both studied species were the fatty acids 16:0; 18:1 Δ9; 20:3 Δ6,9,12, 20:4 Δ5,8,11,14. We found no specificity of compounds in either species. However, G. birdiae, presented higher contents of carotenoids and arachidonic acid than G. domingensis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Climate change can be associated with variations in the frequency and intensity of extreme temperatures and precipitation events on the local and regional scales. Along coastal areas, flooding associated with increased occupation has seriously impacted products and services generated by marine life, in particular the biotechnological potential that macroalgae hold. Therefore, this paper analyzes the available information on the taxonomy, ecology and physiology of macroalgae and discusses the impacts of climate change and local stress on the biotechnological potential of Brazilian macroalgae. Based on data compiled from a series of floristic and ecological works, we note the disappearance in some Brazilian regions of major groups of biotechnological interest. In some cases, the introduction of exotic species has been documented, as well as expansion of the distribution range of economically important species. We also verify an increase in the similarities between the Brazilian phycogeographic provinces, although they still remain different. It is possible that these changes have resulted from the warming of South Atlantic water, as observed for its surface in southeastern Brazilian, mainly during the winter. However, unplanned urbanization of coastal areas can also produce similar biodiversity losses, which requires efforts to generate long-term temporal data on the composition, community structure and physiology of macroalgae.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This work presents the effects of an anatoxin-a(s)-containing extract on a cockroach semi-isolated heart preparation and the results supporting the extract s biological activity on acetylcholinesterase (purified from ell). The presence of the toxin in cyanobacterial strains Anabaena spiroides (ITEP-024, ITEP-025 and ITEP-026) isolated from the Tapacurá reservoir in Pernambuco, Brazil, was confirmed by means of liquid chromatography coupled to an ion-trap mass spectrometer. The anticholinesterase activity was assessed biochemically by the Ellman test and was confirmed by measuring the cockroach s heart rate. The concentration of the extract containing the tested anatoxin-a(s) (antx-a(s)) (10, 16 and 100 μg.μL-1) inhibited the eel acetylcholinesterase (AChE) by more than 90%. The cockroach cardiac frequency increased by a maximum of about 20% within 29 min after the addition of 2.5x10³ μg of extract containing antxa (s).g-1 bw (n=9, p<0.05). Our results strongly indicate that antx-a(s) is capable of exerting biological effects on cockroach, indicating that more research might be conducted to determine its role in the environment, especially on insects.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this study we report the characterization of the volatile compounds of Laurencia dendroidea. Solvent extracts (dichloromethane and methanol), hydrodistillation extracts and headspace solid-phase microextraction samples were obtained and analyzed by GC-MS. Forty-six volatile components were identified in L. dendroidea, among them hydrocarbons, alcohols, phenols, aldehydes, ketones, acids, esters and terpenes.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen) J.V. Lamouroux (Rhodophya), Sargassum cymosum C. Agardh (Heterokontophyta), and Ulva lactuca L. (Chlorophyta), comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU) and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl). The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The concentrations of phycobiliproteins (phycoerythrin and phycocyanin), chlorophyll-a and total soluble proteins were determined monthly in three strains (red, green and brown) of Gracilaria domingensis (Kützing) Sonder ex Dickie, collected from natural populations on the coast of Rio Grande do Norte, Brazil. In all the strains, pigment and protein concentrations were higher in the months of less sunlight and greater nitrogen availability and decreased gradually with increased sunlight and decreased nutrient concentration. The red strain showed higher concentrations of phycoerythrin and total soluble proteins. The difference in the concentration of biochemical components over the course of the year indicates species acclimation to different environmental conditions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The objective of this study was to evaluate the chemical composition, fermentation patterns and aerobic stability of sugarcane silages with addition of amino acid production (monosodium glutamate) by-product (APB) and microbial inoculants. Mature sugarcane was chopped and ensiled in laboratory silos (n = 4/treatment) without additives (control) and with APB (10 g/kg), Pioneer 1174® (PIO, 1.0 mg/kg, Lactobacillus plantarum + Streptoccoccus faecium, Pioneer), Lalsil Cana (2.0 mg/kg, Lactobacillus buchineri, Lallemand) or Mercosil Maís 11C33® (1.0 mg/kg, Lactobacillus buchineri + Lactobacillus plantarum + Streptoccoccus faecium, Timac Agro). Fresh silage and silage liquor samples were obtained to assess pH, chemical composition and organic acid concentrations. Silage temperature was recorded throughout seven days to evaluate aerobic stability. The addition of APB decreased lactic acid levels, increased pH and N-NH3 and did not alter ethanol, acetic and butyric acids concentrations or dry matter (DM) losses. Microbial inoculants enhanced acetic acid levels, although only Pioneer 1174® and Mercosil Maís 11C33® lowered ethanol, butyric acid and DM losses. The addition of APB increased CP content and did not modify DM, soluble carbohydrates contents or in vitro dry matter digestibility. Additives did not alter silage maximum temperature or temperature increasing rate; however, Pioneer 1174® and Mercosil Maís 11C33® increased the time elapsed to reach maximum temperature. Monosodium glutamate production by-product does not alter fermentation patterns or aerobic stability of sugarcane silages, whereas homofermentative bacteria can provide silages of good quality.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

INTRODUCTION: With the aim of searching genetic factors associated with the response to an immune treatment based on autologous monocyte-derived dendritic cells pulsed with autologous inactivated HIV, we performed exome analysis by screening more than 240,000 putative functional exonic variants in 18 HIV-positive Brazilian patients that underwent the immune treatment. METHODS: Exome analysis has been performed using the ILLUMINA Infinium HumanExome BeadChip. zCall algorithm allowed us to recall rare variants. Quality control and SNP-centred analysis were done with GenABEL R package. An in-house implementation of the Wang method permitted gene-centred analysis. RESULTS: CCR4-NOT transcription complex, subunit 1 (CNOT1) gene (16q21), showed the strongest association with the modification of the response to the therapeutic vaccine (p=0.00075). CNOT1 SNP rs7188697 A/G was significantly associated with DC treatment response. The presence of a G allele indicated poor response to the therapeutic vaccine (p=0.0031; OR=33.00; CI=1.74-624.66), and the SNP behaved in a dominant model (A/A vs. A/G+G/G p=0.0009; OR=107.66; 95% CI=3.85-3013.31), being the A/G genotype present only in weak/transient responders, conferring susceptibility to poor response to the immune treatment. DISCUSSION: CNOT1 is known to be involved in the control of mRNA deadenylation and mRNA decay. Moreover, CNOT1 has been recently described as being involved in the regulation of inflammatory processes mediated by tristetraprolin (TTP). The TTP-CCR4-NOT complex (CNOT1 in the CCR4-NOT complex is the binding site for TTP) has been reported as interfering with HIV replication, through post-transcriptional control. Therefore, we can hypothesize that genetic variation occurring in the CNOT1 gene could impair the TTP-CCR4-NOT complex, thus interfering with HIV replication and/or host immune response. CONCLUSIONS: Being aware that our findings are exclusive to the 18 patients studied with a need for replication, and that the genetic variant of CNOT1 gene, localized at intron 3, has no known functional effect, we propose a novel potential candidate locus for the modulation of the response to the immune treatment, and open a discussion on the necessity to consider the host genome as another potential variant to be evaluated when designing an immune therapy study

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The topic of this study is surprise, re gard as an evolutionary complex process, with manifold implication in different fields, from neurological, since aspecific correlate of surprise exist more or less at every level of neuronal processes (e.g. Rao e Ballard, 1999.), to behavioral , inasmuch a s our ability to quickly valuate(assess), recognize and learn from surprising events, are be regarded as pivotal for survival (e.g. Ranganath e Rainer, 2003). In particular this work, going from belief that surprise is really a psychoevolutive mechanism of primary relevance, has the objective to investigate if there may be a substantial connection between development of surprise' emotion and specific developmental problems, or, if in subjects with pervasive developmental disorders surprise may embody (represent) a essential mechanism of emotional tuning, and consequently if abnormalities in such process may be at the base of at least a part of cognitive and behavioural problems that determine (describe) this pathology. Theoretical reasons lead us to conside r this particular pathologic condition, recall to a broad area of research concern the comprehension of belief as marker of ability to reasons about mental states of others (i.e. Theory of Mind), and in addition, at the detection of specific subjects' diff iculty in this field. On the experimental side, as well as limited of this work, we have to compare comprehension and expression of surprise in a sample of 21 children with pervasive developmental disorders (PDD), with a sample of 35 children without deve lopmental problems, in a range of age 3-12. Method After the customary approach to become friendly with the child, an experimenter and an accomplice showed three boxes of nuts, easily to distinguish one from the other because of their different colours an d , working together with the child, the contents of one of the boxes were replaced and a different material (macaroni, pebbles) was put in the box. for the purpose of preparing a surprise for someone. At this stage, the accomplice excused himself/herself and left and the experimenter suggested to the child that he prepare another surprise, replacing the contents in the second box. When the accomplice came back, the child was asked to prepare a surprise for him by picking out the box that he thought was the right one for the purpose. After, and the child doesn't know it, the accomplice change the content of one of the boxes with candies and asked out to the children to open the box, in order to see if he show surprise. Result Date have obtain a significant difference between autistic and normal group, in all four tests. The expression of surprise too, is present in significantly lower degree in autistic group than in control group. Moreover, autistic children do not provide appropriate metarappresentative explanations. Conclusion Our outcome, with knowledge of the limit of our investigation at an experimental level (low number of the champions, no possibility of video registration to firm the expressions ) orient to consider eventuality that surprise, may be seen as relevant component, or indicative, in autistic spectrum disorders.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Il lavoro di tesi di dottorato, dal titolo “Turismo religioso: percorsi culturali-religiosi come leva di sviluppo territoriale”, ha preso in esame in particolare il tema dei percorsi culturali/religiosi, considerati “strategici” in una prospettiva di ricomposizione territoriale e di sviluppo locale, e considerati importanti per la promozione di nuovi flussi turistici e valorizzazione delle risorse storiche, artistiche e culturali del Salento leccese. Il lavoro di tesi affronta il tema del turismo culturale legato all’offerta del bene religioso inteso come potenziale fattore di attrazione turistica ed importante risorsa per lo sviluppo sostenibile del territorio. L’attenzione a santuari e luoghi di culto costituisce, infatti, una valida occasione di interesse per le opere d'arte in essi presenti, e rappresenta anche una possibilità di conoscenza del territorio in cui essi insistono, diventando la destinazione di un turismo colto e di qualità. Il lavoro di tesi, si propone di dimostrare come l’attenzione al motivo religioso creando mobilità, flussi di popolazione, di turisti possa diventare occasione di promozione del prodotto locale, mettendo a sistema tutte le risorse economiche presenti nel territorio. Più in dettaglio, dopo un iniziale approccio teorico al concetto di turismo culturale, turismo religioso e marketing territoriale, esso analizza lo stato dell’arte nel territorio provinciale leccese, individuando possibili itinerari turistico-religiosi nel Salento leccese rapportati ai “Cammini d’Europa”. Si propone l’itinerario turistico - e, in particolare, a quello Leucadense, noto come la “via della Perdonanza di Leuca”, che segue la via dei pellegrinaggi medioevali che si suffragavano di luoghi di sosta in chiese e cappelle dedicate alla Vergine Maria - come strumento verso cui si orientano le recenti strategie di competitività territoriale, definibile come uno strumento d’offerta turistica che mira a valorizzare elementi-risorse del territorio. Si tratta di percorsi utili a promuovere un prodotto competitivo, che presuppone l’enucleazione dell’offerta turistica locale integrata e la costruzione intorno ad essi di un territorio dotato di infrastrutture, ricettività, politiche dell’accoglienza, valorizzazione e fruizione del patrimonio culturale materiale, immateriale ed ambientale. Non mancano nel lavoro preoccupazioni legate alla sostenibilità di un tipo di turismo, che, se di massa (come è il caso delle visite al santuario di San Pio a San Giovanni Rotondo), produce gravi pressioni sull’ambiente e perciò necessita un forte impegno in termini di pubblicità, pianificazione investimenti e presume un’opportuna programmazione da parte degli enti locali in termini di offerta ricettiva, ristorativa e dotazione di infrastrutture. La coerenza degli interventi che promuovono il prodotto religioso non può prescindere da un’integrazione orizzontale tra il sistema territoriale (ambiente, paesaggio, sistemi socio-produttivi) e gli attori locali coinvolti, ai fini di un processo di valorizzazione del patrimonio culturale che produce sviluppo locale.