980 resultados para disc harrows
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ABSTRACTINTRODUCTION:Although deaf people are exposed to hepatitis B and C risk factors, epidemiological studies regarding these diseases in deaf people are lacking.METHODS:After watching an explanatory digital versatile disc (DVD) in Brazilian Sign Language, 88 deaf people were interviewed and tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), hepatitis B core antibody (anti-HBc), and hepatitis C virus antibody (anti-HCV).RESULTS:The prevalence of hepatitis B markers was 8%; they were associated with incarceration and being born outside the State of São Paulo. No cases of hepatitis C were identified.CONCLUSIONS:Participants showed a substantial lack of knowledge regarding viral hepatitis, indicating a need for public policies that consider linguistic and cultural profiles.
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Abstract INTRODUCTION: The aim of this study was to determine whether an herbal extract containing monoterpene exhibited activity against multidrug-resistant Staphylococcus aureus and Pseudomonas aeruginosa isolated from clinical infection samples. METHODS: The essential oil of Trachyspermum ammi (L.) Sprague ex Turrill (Apiaceae) fruit was extracted by hydrodistillation. Fruit residues were treated with hydrochloric acid and re-hydrodistilled to obtain volatile compounds. Compounds in the distilled oil were identified using gas-chromatography (GC) and GC-mass spectrometry (MS). The antibiotic susceptibility of all bacterial isolates was analyzed using both the disc diffusion method and determination of the minimum inhibitory concentration (MIC). The sensitivity of antibiotic-resistant isolates to essential oil was also determined by using the disc diffusion method and MIC determination. RESULTS: Of 26 clinical isolates, 92% were multidrug-resistant (MDR). Aromatic monoterpenes (thymol, paracymene, and gamma-terpinene) were the major (90%) components of the oil. Growth of S. aureus strains was successfully inhibited by the oil, with an inhibitory zone diameter (IZD) between 30-60mm and MIC <0.02μL/mL. The oil had no antimicrobial activity against clinical isolates of P. aeruginosa; rather, it prevented pigment production in these isolates. CONCLUSIONS: This study revealed that the essential oil of Trachyspermum ammi, which contains monoterpene, has good antibacterial potency. Monoterpenes could thus be incorporated into antimicrobial ointment formulas in order to treat highly drug-resistant S. aureus infections. Our findings also underscore the utility of research on natural products in order to combat bacterial multidrug resistance.
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Due to the fact that different injection molding conditions tailor the mechanical response of the thermoplastic material, such effect must be considered earlier in the product development process. The existing approaches implemented in different commercial software solutions are very limited in their capabilities to estimate the influence of processing conditions on the mechanical properties. Thus, the accuracy of predictive simulations could be improved. In this study, we demonstrate how to establish straightforward processing-impact property relationships of talc-filled injection-molded polypropylene disc-shaped parts by assessing the thermomechanical environment (TME). To investigate the relationship between impact properties and the key operative variables (flow rate, melt and mold temperature, and holding pressure), the design of experiments approach was applied to systematically vary the TME of molded samples. The TME is characterized on computer flow simulation outputsanddefined bytwo thermomechanical indices (TMI): the cooling index (CI; associated to the core features) and the thermo-stress index (TSI; related to the skin features). The TMI methodology coupled to an integrated simulation program has been developed as a tool to predict the impact response. The dynamic impact properties (peak force, peak energy, and puncture energy) were evaluated using instrumented falling weight impact tests and were all found to be similarly affected by the imposed TME. The most important molding parameters affecting the impact properties were found to be the processing temperatures (melt andmold). CI revealed greater importance for the impact response than TSI. The developed integrative tool provided truthful predictions for the envisaged impact properties.
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The severity and frequency of opportunistic fungal infections still growing, concomitantly to the increasing rates of antimicrobial drugs resistance. Natural matrices have been used over years due to its multitude of health benefits, including antifungal potential. Thus, the present work aims to evaluate the anti-Candida potential of the phenolic extract and individual phenolic compounds of Glycyrrhiza glabra L. (licorice), by disc diffusion assay, followed by determination of the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for both planktonic cells and biofilms. Licorice extract evidenced inhibitory potential against the nineteen tested Candida strains, but no pronounced effect was observed by testing the most abundant individual phenolic compounds. Candida tropicalis strains were the most sensible, followed by Candida glabrata, Candida parapsilosis and, then, Candida albicans. Lower MIC and MFC values were achieved to C. glabrata and C. tropicalis, which confirms its susceptibility to licorice extract; however, for C. tropicalis strains a higher variability was observed. Anti-biofilm potential was also achieved, being most evident in some C. glabrata and C. tropicalis strains. In general, a twice concentration of the MIC was necessary for planktonic cells to obtain a similar potential to that one observed for biofilms. Thus, an upcoming approach for new antifungal agents, more effective and safer than the current ones, is stablished; notwithstanding, further studies are necessary in order to understand its mechanism of action, as also to assess kinetic parameters.
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This study characterized morphologically Trichodina heterodentata Duncan, 1977 from cultivated fingerlings of "pirarucu" Arapaima gigas in Peru. Body and gill smears were air-dried at room temperature, impregnated with silver nitrate and/or stained with gomori trichromic. Prevalence was 100%. Trichodina heterodentata was considered a medium-sized trichodinid with mean body diameter of 56.0+ 5.25 (47.3-76.0) μm, denticulate ring 28.21± 2.71 (20-34.7) μm, adhesive disc 45.7±3.8 (37.1-57.3) μm diameter and number of denticles of 20.7± 2.6 (12-24). The present study reports not only the first occurrence of T. heterodentata in Peru but also the first record of this trichodinid infesting A. gigas. Camparative tables of all reports of T. heterodentata are also presented.
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Programa Doutoral em Engenharia Biomédica
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This project focused on the investigation and the development of a chemical sensing system for the determination of chromium Cr6+ and a bio-reactor followed by electrochemical detection at a glassy carbon electrode, for the determination of organochlorine compounds. The conjugation of Cr6+ with 1,5-diphenylcarbazide was studied at various types of electrodes such as glassy carbon, ultra-trace epoxy-graphite, chemically or un-modified carbon-paste and dropping-mercury. The cyclic voltammetric behaviour of the complex was also investigated. In addition, the possibility of developing a chemical sensor, Le. an electrochemical probe capable of sensing Cr6+ through its complexation with 1,5-diphenylacarbazide was studied. The conjugations of l-chloro-2,4-dinitrobenzene, 2,4-dichloronitrobenzene and ethacrynic, which are electrophilic organochlorine compounds, with reduced glutathione, were studied in order to test the bioreactor developed, based on the immobilisation of glutathione s-transferase. This was carried out at different types of electrodes such as glassy-carbon, gold, silver, platinum, epoxy-graphite, hangingmercury, and ferrocene-modified rotating-disc electrodes.
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There are presently over 182 RBC plants, treating domestic wastewater, in the Republic of Ireland, 136 of which have been installed since 1986. The use of this treatment plant technology, although not new, is becoming increasingly popular. The aim of this research was to assess the effects that a household detergent has on rotating biological contractor treatment plant efficiency. Household detergents contribute phosphorus to the surrounding environment and can also remove beneficial biomass from the disc media. A simple modification was made to a conventional flat disc unit to increase the oxygen transfer of the process. The treatment efficiency of the modified RBC (with aeration cups attached) was assessed against a parallel conventional system, with and without degergent loading. The parameters monitored were chemical oxygen demand (COD), bio-chemical oxygen demand (BOD), nitrates, phosphates, dissolved oxygen, the motors power consumption, pH, and temperature. Some microscopic analysis of the biofilm was also to be carried out. The treatment efficiency of both units was compared, based on COD/BOD removal. The degree of nitrification achievable by both units was also assessed with any fluctuations in pH noted. Monitoring of the phosphorus removal capabilities of both units was undertaken. Relationships between detergent concentrations and COD removal efficiencies were also analysed.
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A preliminary account on the normal development of the imaginai discs in holometabolic Insects is made to serve as an introduction to the study of the hereditary homoeosis. Several facts and experimental data furnished specially by the students of Drosophila are brought here in searching for a more adequate explanation of this highly interesting phenomenon. The results obtained from the investigations of different homoeotic mutants are analysed in order to test Goldschmidt's theory of homoeosis. Critical examination of the basis on which this theory was elaborated are equally made. As a result from an extensive theoretical consideration of the matter and a long discussion of the most recent papers on this subject the present writer concludes that the Goldschmidt explanation of the homoeotic phenomena based on the action of diffusing substances produced by the genes, the "evocators", and on the alteration of the normal speed of maturation of the imaginai discs equally due to the activity of the genes, could not be proved and therefore should be abandoned. In the same situation is any other explanation like that of Waddington or Villee considered as fundamentally identical to that of Goldschmidt. In order to clear the problem of homoeosis in terms which seem to put the phenomenon in complete agreement with the known facts the present writer elaborated a theory first published a few years ago (1941) based entirely on the assumption that the imaginai discs are specifically determined by some kind of substances, probably of chemical nature, contained in the cytoplam of the cells entering in the consti- tution of each individual disc. These substances already present in the blastem of the egg in which they are distributed in a definite order, pass to different cells at the time the blastem is transformed into blastoderm. These substances according to their organogenic potentiality may be called antenal-substance, legsubstance, wing-substance, eye-substance, etc. The hipoderm of the embryo resulting from the multiplication of the blastoderm cells would be constituted by a series of cellular areas differing from each other in their particular organoformative capacity. Thus the hypoderm giving rise to the imaginai discs, it follows that each disc must have the same organogenic power of the hypodermal area it came from. Therefore the discs i*re determinated since their origin by substances enclosed in the cytoplasm of their cells and consequently can no longer alter their potentiality. When an antennal disc develops into a leg one can conclude that this disc in spite of its position in the body of the larva is not, properly speaking, an antennal disc but a true leg disc whose cells instead of having in their cytoplasm the antennal substance derived from the egg blastem have in its place the leg-substance. Now, if a disc produces a tarsus or an antenna or even a compound appendage partly tarsus-like, partly antenna-like, it follows tha,t both tarsal and antennal substances are present in it. The ultimate aspect of the compound structure depends upon the reaction of each kind of substance to the different causes influencing development. For instance, temperature may orient the direction of development either lowards arista or tarsus, stimulating, or opposing to the one or the other of these substances. Confering to the genes the faculty of altering the constitution of the substances containing in the cytoplasm forming the egg blastem or causing transposition of these substances from one area to another or promoting the substitution of a given substance by a different one, the hereditary homoeocis may be easily explained. However, in the opinion of the present writer cytoplasm takes the initiative in all developmental process, provoking the chromosomes to react specifically and proportionally. Accordingly, the mutations causing homoeotic phenomena may arise independently at different rime in the cytoplasm and in the chromosomes. To the part taken by the chromosomes in the manifestation of the homoeotic characters is due the mendalian ratio observed in homoeotic X normal crosses. Expression, in itself, is mainly due to the proportion of the different substances in the cells of the affected discs. Homoeotic phenomena not presenting mendelian ratio may appear as consequence of cytoplasmic mutation not accompanied by chromosomal mutation. The great variability in the morphology of the homoeotic characteres, some individual being changed towards an extreme expression of the mutant phenotype while others in spite of their homozigous constitution cannot be distinguished from the normal ones, strongly supports the interpretation based on the relative proportion of the determining substances in the discs. To the same interpretation point also asymetry and other particularities observed in the exteriorization of the phenomenon. In conformity with this new conception homoeosis should not prove homology of Insect appendages (Villee 1942) since a more replacement of substances may cause legs to develop in substitution of the wings, as it was already observed (requiring confirmation in the opinion of Bateson 1894, p. 184) and no one would conclude for the homology of these organs in the usual meaning of the term.
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This paper deals with anatomical descriptions of some types of nectaries in 27 species of honey plants of Piracicaba, S. P. The material studied was divides in two groups: a) Extra-floral nectaries; b) Floral nectaries. Euphorbia pulcherrima, Willd; showed to belonging to the first group: its nectaries tissue consist of an epidermal layer of cell without stomata and with true gland, with subepidermal cells diferentiated by the thickness of the wall. Among the plants with floral nectaries, the following types has been listed, according the location of the nectary in the flower: 1 - with true glands: a) in sepals, Hibiscus rosa sinensis, L.; Dombeya Wallichii, Bth. e Hk; b) in the stamens tube, Antigonum leptopus, Hook e Arn.; 2 - on the receptacle with nectariferous tissue in the epidermal cell with: a) thickness wall with stomata, Prunus persical, L.; b) thin wall without stomata, Crotalaria paulinia, Shranck; Caesal-pinia sepiaria, Roxb; Aberia caffra; 3 - with a disc located in the receptacle with: epidermal: a) with stomata, Coffea arábica, L. var. semper florens; Citrus aurantifolia, Swing; Cinchona sp.; Pryrostegia ignea, Presl.; b) without stomata and with thin wall, Leojurus sibiricus, L.; Bactocydia unguis, Mart., Ipomoea purpurea, L.; Greviüea Thelemanniana, Hueg.; Dolichos lablab, L.; Vernonia polyanthes, Less., Montanoa bipinatifida, C. Koch., Eruca sativa, L. Brassica Juncea, Co; Eucalyptus tereticomis, Smith.; Eucalyptus rostrata, Schleche; Salvia splendens, Selow.; 4 - in the basal tissues of the ovary, Budleia brasiliensis, Jacq F.; Petrea subserrata, Cham.; 5 - in the base of stamens, Per sea americana, Mill. On the anatomical point of view, most of the types of nectary studied has external nectariferous tissues, located on the epidermal cells with thin periclinal wall and without stomata. The sub-epidermal layer were rich in sugar. Short correlation was found between the structure of the nectary and the amount of nectar secretion. So, in the nectary with true glands, in those with thin wall and without stomata on epidermal cells and in those with stomata, the secretion was higher than in the other types listed.
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The tadpole of Hypsiboas atlanticus (Caramaschi & Velosa, 1996) is described from the municipality of Maceió, State of Alagoas, Brazil. At stage 36 the larvae have an overall elliptical body in lateral and dorsal views, oral disc anteroventral, spiracular tube sinistral, and labial tooth row formula 2(1,2)/3(1). The oral disc is surrounded, almost completely (anterior medial gap present) by a single row of marginal papillae. Described tadpoles of the H. punctatus species group can be differentiated by a combined disc oral features. Additional descriptions of H. punctatus (Schneider, 1799) tadpoles from populations throughout South America may be helpful in determining the status of these populations.
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Purpose: To investigate the accuracy of 4 clinical instruments in the detection of glaucomatous damage. Methods: 102 eyes of 55 test subjects (Age mean = 66.5yrs, range = [39; 89]) underwent Heidelberg Retinal Tomography (HRTIII), (disc area<2.43); and standard automated perimetry (SAP) using Octopus (Dynamic); Pulsar (TOP); and Moorfields Motion Displacement Test (MDT) (ESTA strategy). Eyes were separated into three groups 1) Healthy (H): IOP<21mmHg and healthy discs (clinical examination), 39 subjects, 78 eyes; 2) Glaucoma suspect (GS): Suspicious discs (clinical examination), 12 subjects, 15 eyes; 3) Glaucoma (G): progressive structural or functional loss, 14 subjects, 20 eyes. Clinical diagnostic precision was examined using the cut-off associated with the p<5% normative limit of MD (Octopus/Pulsar), PTD (MDT) and MRA (HRT) analysis. The sensitivity, specificity and accuracy were calculated for each instrument. Results: See table Conclusions: Despite the advantage of defining glaucoma suspects using clinical optic disc examination, the HRT did not yield significantly higher accuracy than functional measures. HRT, MDT and Octopus SAP yielded higher accuracy than Pulsar perimetry, although results did not reach statistical significance. Further studies are required to investigate the structure-function correlations between these instruments.
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Cultured primary fetal cells from one organ donation could possibly meet the exigent and stringent technical aspects for development of therapeutic products. These cell types have fewer technological limitations for cellular proliferation capacity (simple culture conditions) and maintenance of differentiated phenotype, and they also have low probability for transmission of communicable diseases. Master and Working Cell Banks (MCB, WCB) can be obtained from one fetal organ donation, permitting multiple tissues (skin, bone, cartilage, muscle and intervertebral disc) to be processed in short periods of time with identical methods to assure a stringent tracing of the processes for the production of standardized therapeutic agents. Clinical use of biologics from embryo and fetal tissues is relatively new and current legislation and ethics have some differences between countries to date. In addition, specific cell delivery systems for each tissue type can be adapted to the clinical application. Since it is the intention that banked primary fetal cells enhance the prospective treatment of hundreds of thousands of patients with only one organ donation, it is imperative to show consistency, traceability and safety of the processes including donor tissue selection, cell banking, cell testing and growth of cells in out-scaling for the preparation of bio-engineered products for clinical application.
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BACKGROUND: Drusen of the optic disc are associated with slowly progressive optic neuropathy, characterized by accumulation of acellular laminated concretions in the prelaminar portion of the optic nerve. Papillary hemorrhages and vascular shunts have been reported with disc drusen but their frequency and clinical significance is not well known. METHODS: Retrospective study of fundus photographs of 116 patients with disc drusen referred to the National Hospital for Neurology and Neurosurgery, London, between 1965 and 1991. RESULTS: Hemorrhages were found in 23 eyes from 16/116 (13.8%) patients. Most cases (68.8%, 11/16 cases) occurred in patients with buried drusen, and most hemorrhages were deeply located. Vascular shunts were present in 6.9% (8/116 cases), most frequently in patients with exposed drusen (6/8 cases), most being of the venous type (7/8 cases). DISCUSSION: Vascular anomalies are not rare in disc drusen, as 20.7% (24/116 cases) of our patients presented either disc hemorrhages or shunt vessels. Their presence supports the hypothesis of the slowly progressive nature of disc drusen and the more advanced stage of optic neuropathy in such eyes.
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El Port d'Informació Científica és un centre de Computació Grid de referència que dona suport a comunitats científiques, com el LHC (CERN). Al PIC, trobem una gran varietat de tecnologies que proporcionen serveis al centre. Des de l'arquitectura i elements de la xarxa, fins a recursos informàtics de computació, sistemes d'emmagatzematge a disc i cinta magnètica, bases de dades (ORACLE/PostgreSQL). El projecte consisteix en el disseny i implementació d'una base de dades col·lectora de tota la informació rellevant dels diferents sistemes del centre, i un portal web on mostrar tots els valors i gràfiques, tot basat en programari lliure.