952 resultados para Low cost alternatives
Resumo:
Background: Echocardiography, though non-invasive and having relatively low-cost, presents issues of variability which can limit its use in epidemiological studies. Objective: To evaluate left ventricular mass reproducibility when assessed at acquisition (online) compared to when assessed at a reading center after electronic transmission (offline) and also when assessed by different readers at the reading center. Methods: Echocardiographers from the 6 ELSA-Brasil study investigation centers measured the left ventricular mass online during the acquisition from 124 studies before transmitting to the reading center, where studies were read according to the study protocol. Half of these studies were blindly read by a second reader in the reading center. Results: From the 124 echocardiograms, 5 (4%) were considered not measurable. Among the remaining 119, 72 (61%) were women, mean age was 50.2 ± 7.0 years and 2 had structural myocardial abnormalities. Images were considered to be optimal/ good by the reading center for 110 (92.4%) cases. No significant difference existed between online and offline measurements (1,29 g, CI 95% −3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85). For images read by two readers, the intraclass correlation coefficient was 0.86 (CI 95% 0.78-0.91). Conclusion: There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies. Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.
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Studying the application of those methods of microanalysis which avoid costly instalations and atempting to combine high precision with low cost, the author recomends a new method consisting of the following : a) exposure of a surface of 530.66 mm2 of Zn to the action of the acid. b) instalation of 3 series of HgBr2 paper in test tubes with an internal diameter of respectively 3,5 and 9 mm. c - mouting between two slides, covering the margins (with parafin etc.) with parafin in order to conserve the results of the determination without change due to the action of light or moisture. d) the results can be compared at a level of 0.00001 mgr. A203 or 0.000007575 mgr. As.
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In this paper the A. A. report the observations about the general anesthesia by chloral hydrate on the veterinary surgery. The observations were made on emasculation practices of horses, mules and hogs. It was possible to establish the following conclusions: 1) The choral hydrate presents low cost, it harmless, and is of easy application. 2) The more recommendable dosis for equine and swine were : 12-13 g per 100 k of body weight, in destilled water solution at 30 and 20%, respectively. 3) The anaethestic was injected by intravenous way with good results; in horses and mules the applications were made in the jugular; in swine, in the anterior vena cava, as was described by Carle and Dewhirst, because it was impracticable in the ear vein. 4) The dosis applied produced deep narcosis not lasting to long and with no danger to the animal's life. 5) In the case of fattening hogs, it must be made a discount of about 40% on the body weight, to calculate dosis to be employed. 6) The tables A and B show the results, that may be considered as good.
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Aspects related to the longevity and oviposition of Ophyra albuquerquei Lopes, 1985 are studied. Males had a mean lifespan longer than females (40.24 vs. 33.15 days, respectively), while still possessing qualitative advantages during this period. Females O. albuquerquei were fed on powdered milk, fish flour, refined sugar and water, and provided fish flour and moistened sawdust for oviposition. The length of the oviposition period for females was 46.75 days, and most of the deposition of the eggs occurred in the first days of the colony. Females completed 50% of their egg deposition by Day 16, seven days before the large last mortality peak and about 12 days after the first oviposition in the colony. Females deposited an average of 184 eggs per individual. Mortality of males, unlike females, was low until the 28th day, and increased thereafter. It was demonstrated that it is possible to maintain colonies of this species under laboratory conditions for at least 28 days with high fertility and low cost.
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We study how the heterogeneity of agents affects the extent to which changes in financial incentives can pull a group out of a situation of coordination failure. We focus on the connections between cost asymmetries and leadership. Experimental subjects interact in groups of four in a series of weak-link games. The treatment variable is the distribution of high and low effort cost across subjects. We present data for one, two and three low-cost subjects as well as control sessions with symmetric costs. The overall pattern of coordination improvement is common across treatments. Early coordination improvements depend on the distribution of high and low effort costs across subjects, but these differences disappear with time. We find that initial leadership in overcoming coordination failure is not driven by low-cost subjects but by subjects with the most frequent cost. This conformity effect can be due to a kind of group identity or to the cognitive simplicity of acting with identical others.
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Los requisitos de los dispositivos empleados en los nuevos sistemas de telecomunicaciones son: unas avanzadas prestaciones, reducido tamaño y bajo coste. Actualmente, se utilizan filtros basados en la tecnología SAW para trabajar a frecuencias de microondas. Dado los inconvenientes que presentan dicho tipo de filtros, se pretende substituirlos por filtros basados en tecnología BAW. La topología en escalera es hasta el momento la más extendida para diseñar estos filtros.
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Aquest projecte té com a objectiu l'anàlisi de prestacions de processadors RISC de baix cost i el disseny d'un processador RISC simple per a aplicacions de propòsit general relacionades amb l'adquisició i el procés simple de dades. Com a resultat es presenta el processador SR3C de 32 bits i arquitectura RISC. Aquest processador s'ha descrit i simulat mitjançant el llenguatge de descripció de hardware VHDL i s'ha sintetitzat en una FPGA. El processador està preparat per poder utilitzar-se en SoCs reals gràcies al compliment de l'estàndard de busos Wishbone. A més també es pot utilitzar com plataforma educativa gràcies a l'essamblador i simulador desenvolupats.
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For many drugs, finding the balance between efficacy and toxicity requires monitoring their concentrations in the patient's blood. Quantifying drug levels at the bedside or at home would have advantages in terms of therapeutic outcome and convenience, but current techniques require the setting of a diagnostic laboratory. We have developed semisynthetic bioluminescent sensors that permit precise measurements of drug concentrations in patient samples by spotting minimal volumes on paper and recording the signal using a simple point-and-shoot camera. Our sensors have a modular design consisting of a protein-based and a synthetic part and can be engineered to selectively recognize a wide range of drugs, including immunosuppressants, antiepileptics, anticancer agents and antiarrhythmics. This low-cost point-of-care method could make therapies safer, increase the convenience of doctors and patients and make therapeutic drug monitoring available in regions with poor infrastructure.
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The quintessence of recent natural science studies is that the 2 degrees C target can only be achieved with massive emission reductions in the next few years. The central twist of this paper is the addition of this limited time to act into a non-perpetual real options framework analysing optimal climate policy under uncertainty. The window-of-opportunity modelling setup shows that the limited time to act may spark a trend reversal in the direction of low-carbon alternatives. However, the implementation of a climate policy is evaded by high uncertainty about possible climate pathways.
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Electroencephalography is mandatory to determine the epilepsy syndrome. However, for the precise localization of the irritative zone in patients with focal epilepsy, costly and sometimes cumbersome imaging techniques are used. Recent small studies using electric source imaging suggest that electroencephalography itself could be used to localize the focus. However, a large prospective validation study is missing. This study presents a cohort of 152 operated patients where electric source imaging was applied as part of the pre-surgical work-up allowing a comparison with the results from other methods. Patients (n = 152) with >1 year postoperative follow-up were studied prospectively. The sensitivity and specificity of each imaging method was defined by comparing the localization of the source maximum with the resected zone and surgical outcome. Electric source imaging had a sensitivity of 84% and a specificity of 88% if the electroencephalogram was recorded with a large number of electrodes (128-256 channels) and the individual magnetic resonance image was used as head model. These values compared favourably with those of structural magnetic resonance imaging (76% sensitivity, 53% specificity), positron emission tomography (69% sensitivity, 44% specificity) and ictal/interictal single-photon emission-computed tomography (58% sensitivity, 47% specificity). The sensitivity and specificity of electric source imaging decreased to 57% and 59%, respectively, with low number of electrodes (<32 channels) and a template head model. This study demonstrated the validity and clinical utility of electric source imaging in a large prospective study. Given the low cost and high flexibility of electroencephalographic systems even with high channel counts, we conclude that electric source imaging is a highly valuable tool in pre-surgical epilepsy evaluation.
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The present report describes an alternative method for in vitro detection of HIV-1 -specific antibody secretion in 24h of culture employing as stimulant of peripheral blood mononuclear cells the disrupted inactivated whole virus adsorbed onto microwells in a commercial ELISA kit plates. The results obtained from this technique have showed high sensitivity and specificity since it was capable of detecting HIV-1 infection early after birth. There were neither false-positivity nor false-negativity when blood samples obtained from HIV-1 seronegative asymptomatic individuals, and HIV-1 seropositive adult patients were analized. This rapid, low cost, simple, highly sensitive and specific assay can be extremely useful for early diagnosis of pediatric HIV infection.
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Treball de recerca realitzat per alumnes d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. Aquest treball es tracta en la creació d’un projecte empresarial, és a dir, d’una planificació estratègica que afecta a tots els àmbits de la empresa al llarg d’un període de temps i que té per objectiu analitzar la viabilitat, examinar els objectius i descobrir els inconvenients del mateix. En concret s’ha projectat és un hostal ‘low cost’. Alhora de comprovar la viabilitat del projecte, s’han hagut de realitzar els tests corresponents per saber si tindria èxit o no. I tots han demostrat un resultat factible, ja que, encara que van sorgir problemes amb l’acceptació d’aquest nou estil, concretament en el fet d’haver de compartir habitació amb altres persones, al poder oferir altres tipus d’habitacions i en el cas de compartir habitació donar molta seguretat, els anàlisis ens han donat uns resultats acceptables. S’han realitzat també quadres financers, préstecs, calculat les despeses d’inici d’empresa i de manteniment, publicitat, despeses de personal, i finalment aquest també han donat un resultat de viabilitat positiu.
Resumo:
En una época como la actual, en la que se hace necesario disponer de equipos con grandes características y recursos para poder disfrutar de los últimos lanzamientos en juegos, no dejan de producirse equipos de bajo coste basados en microcontroladores que pueden entretener al mismo nivel que los más caros. Este proyecto reúne el diseño de la configuración, interconexión y programación de código necesarios para ejecutar un juego sencillo. Para ello se ha utilizado una pantalla LCD táctil y un microcontrolador HCS12.
Resumo:
En els últims anys printed electronics està aixecant un gran interès entre la indústria electrònica. Aquest tipus de procés consisteix en imprimir circuits amb tècniques d'impressió convencionals utilitzant tintes conductores, resistives, dielèctriques o semiconductores sobre substrats flexibles de baix cost com paper o plàstic. Fer servir aquestes tècniques s'espera que suposi una reducció dels costos de producció degut a que és un procés totalment additiu el que fa que sigui més senzill i es redueixi la quantitat de material emprat. El disseny de dispositius bàsics com resistències, condensadors i bobines per posteriorment veure la relació entre simulacions i valors obtinguts ha ocupat la primera part del projecte. La segona s’ha centrat en fer prototips d’antenes per a RFID (Radio Frequency IDentification) amb la tecnologia que es disposa a CEPHIS (Centre de Prototips i Solucions Hardwre-Software). Tot això ha servit per caracteritzar la tecnologia de la que es disposa i saber en quins apartats s’ha de seguir treballant per aconseguir millors prestacions.
Resumo:
Treball de recerca realitzat per alumnes d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. Aquest treball és una creació d’un projecte empresarial, és a dir, una planificació estratègica que té per objectiu analitzar la viabilitat, examinar els objectius i descobrir els inconvenients del mateix. Aquest projecte final està enfocat al turisme i consisteix en crear una agència de viatges. S’ha decidit crear una agència de viatges de baix cost destinada principalment als joves, ja que aquest sector de població busca una manera de viatjar econòmica que combini diversió i cultura. El treball es basa en la recerca i aplicació de la informació sobre la idea inicial. En primer lloc, per tal de realitzar-lo s’ha fet un projecte d’empresa, un estudi de mercat i de l’entorn amb les seves corresponents enquestes i un pla de marketing. En segon lloc, s’ha realitzat una definició del mercat i la comunicació, una determinació dels preus i organització de les vendes així com una identificació i organització de l’empresa i els seus productes. Per últim, s’ha fet un estudi econòmic i financer del projecte i, les conclusions extretes d’aquest, diuen que el nostre projecte serà viable i tindrà un èxit tècnic.