5 resultados para INFECTION-RATES
em Reposit
Resumo:
Recent epidemiologic studies clearly outline the link between fungal sensibilization and exarcebations of asthma, leading to increased morbidity and mortality. Amongst the filamentous fungi, Aspergillus scpecies have been strongly linked with exarcebations of asthma and other respiratory allergic diseases. Particles of approximately 1 to 4 pm are deposited in the lower respiratory tract. Therefore, conidia of A. fumigatus are small enough to traverse the terminal respiratory airways and reach the pulmonary alveoli, whereas the larger conidia of some other Aspergillus species, such as A. flavus and A. niger, tend to be deposited in the paranasal sinuses and upper airways. Exposute to environmental fungal spores has been associated with worsening asthma symptoms, lung function, hospital admissions and asthma-related deaths.
Resumo:
X-ray fluoroscopy is essential in both diagnosis and medical intervention, although it may contribute to significant radiation doses to patients that have to be optimised and justified. Therefore, it is crucial to the patient to be exposed to the lowest achievable dose without compromising the image quality. The purpose of this study was to perform an analysis of the quality control measurements, particularly dose rates, contrast and spatial resolution of Portuguese fluoroscopy equipment and also to provide a contribution to the establishment of reference levels for the equipment performance parameters. Measurements carried out between 2007 and 2013 on 143 fluoroscopy equipment distributed by 34 nationwide health units were analysed. The measurements suggest that image quality and dose rates of Portuguese equipment are congruent with other studies, and in general, they are as per the Portuguese law. However, there is still a possibility of improvements intending optimisation at a national level.
Resumo:
Urinary tract infection (UTI) is one of the most prevalent pathologies in developed countries, particularly in women, characterized by the presence of bacterial growth in any part of the urinary system. Currently, urine culture is considered the gold standard method for the diagnosis of UTI. However, this method has several disadvantages including the time necessary for obtaining the results and the associated high costs. Therefore, it is important to evaluate new efficient and valuable methods for the diagnosis of these infections. Objectives: Presently, dipsticks are considered a possible valuable alternative to urine culture. This method has very low costs associated and the results can be obtained in few minutes. Here we aim to compare the sensibility, specificity, predictive value of a positive test and a negative test of both methods in order to determine the efficiency of the test strips method and also to characterize the microorganism more frequently isolated.
Resumo:
Cellulose and its derivatives, such as hydroxypropylcellulose (HPC) have been studied for a long time but they are still not well understood particularly in liquid crystalline solutions. These systems can be at the origin of networks with properties similar to liquid crystalline (LC) elastomers. The films produced from LC solutions can be manipulated by the action of moisture allowing for instance the development of a soft motor (Geng et al., 2013) driven by humidity. Cellulose nanocrystals (CNC), which combine cellulose properties with the specific characteristics of nanoscale materials, have been mainly studied for their potential as a reinforcing agent. Suspensions of CNC can also self-order originating a liquid-crystalline chiral nematic phases. Considering the liquid crystalline features that both LC-HPC and CNC can acquire, we prepared LC-HPC/CNC solutions with different CNC contents (1,2 and 5 wt.%). The effect of the CNC into the LC-HPC matrix was determined by coupling rheology and NMR spectroscopy - Rheo-NMR a technique tailored to analyse orientational order in sheared systems. (C) 2015 Elsevier Ltd. All rights reserved.
Resumo:
Since long ago cellulosic lyotropic liquid crystals were thought as potential materials to produce fibers competitive with spidersilk or Kevlar, yet the processing of high modulus materials from cellulose-based precursors was hampered by their complex rheological behavior. In this work, by using the Rheo-NMR technique, which combines deuterium NMR with rheology, we investigate the high shear rate regimes that may be of interest to the industrial processing of these materials. Whereas the low shear rate regimes were already investigated by this technique in different works [1-4], the high shear rates range is still lacking a detailed study. This work focuses on the orientational order in the system both under shear and subsequent relaxation process arising after shear cessation through the analysis of deuterium spectra from the deuterated solvent water. At the analyzed shear rates the cholesteric order is suppressed and a flow-aligned nematic is observed which for the higher shear rates develops after certain time periodic perturbations that transiently annihilate the order in the system. During relaxation the flow aligned nematic starts losing order due to the onset of the cholesteric helices leading to a period of very low order where cholesteric helices with different orientations are forming from the aligned nematic, followed in the final stage by an increase in order at long relaxation times corresponding to the development of aligned cholesteric domains. This study sheds light on the complex rheological behavior of chiral nematic cellulose-based systems and opens ways to improve its processing. (C) 2015 Elsevier Ltd. All rights reserved.