Three different water classification techniques were applied to classify all mineral waters in Portugal from which chemical analysis were found in the literature. The three techniques were ...hierarchical clustering as can be applied from the Statistical Package for the Social Sciences and two empirical techniques, one based primarily on chemical properties of the waters and one based primarily on hydrological properties. The three methods were compared and it was found that there was a reasonable overlap between the hierarchical clustering and the classification method based primarily on chemical properties, while the hydrological technique showed systematic differences. The results from all classifications are plotted on block maps to indicate areas where different water types are dominant. It is concluded that for the general classification of mineral waters in Portugal the empirical techniques are most usable as newly discovered mineral waters can easily be fitted into the classification, while a new calculation, inferring the risk of samples moving from one to another cluster, needs to be made if hierarchical clustering is applied. Considering the fact that often chemical characterization of mineral waters is used in discussions it is suggested that the classification method based on chemical characteristics is perhaps the most useful to apply to Portuguese mineral waters. The empirical classification techniques can also be applied easily to mineral water sets from other regions than Portugal.
•Portugal has a very large number of mineral waters with a very variable chemistry.•The diversity is related to geology which defines the composition of these waters.•Three different classification methods are compared to assess this variability.•Maps are prepared that show variability between samples and classification methods.
The present research evaluates the sensitivity and salience of form–function correlations in contrast with other types of feature correlations (function–function, form–form) in adults and using real ...object features (from tools and utensils). In Experiment 1, the participants judged the relation between the form and function features of tools. In Experiment 2, participants were asked to generate a second feature related to a given form or function feature. In Experiment 3, participants were asked to make a lexical decision in which form and function features were used as primes and targets. The results showed that even though participants were sensitive to form–function correlations, these were not particularly salient when compared with other feature-type correlations, notably function–function correlations. Our data underline the overall importance of function information to object representations and the impact of the statistical co-occurrence of features when processing object features.
To study the clinical benefit of low-level light therapy when associated with intense pulsed light for the treatment of meibomian gland dysfunction.
An observational study. Two groups of patients ...that were treated with IPL were considered: group 1 (31 subjects, 62 eyes), intense pulsed light followed by low-level light therapy and group 2 (31 subjects, 62 eyes) intense pulsed light alone. In both groups, treatments were performed in 3 sessions and subjects were evaluated at baseline and 3 weeks after the last treatment session. Values are shown as mean difference ± standard deviation.
We observed a significant improvement in OSDI-12 score and lipid layer thickness, in both groups (-22.7±17.5, p<0.001 in group 1 and -23.6±23.8, p<0.001 in group 2 for OSDI and +18.6 ± 37.0, p<0.001 in group 1 and +19.9 ± 26.4, p<0.001 in group 2 for lipid layer thickness). Despite no differences between groups at baseline (p=0.469), only group 1 had a significant improvement in Schirmer test (+1.6±4.8, p=0.009 in group 1 and +1.7±6.9, p=0.057 in group 2). No significant side effects were noted. No patient in any group felt subjectively "worse" after the treatment.
Intense pulsed light seems effective and safe for the treatment of meibomian gland dysfunction, improving symptoms and the tear film lipid layer. This study shows no strong evidence of the benefit of low-level light therapy, but it shows weak evidence that it may further improve aqueous tear production.
Data from neuropsychological research suggest that categorizing objects at different levels of specificity requires different cognitive and neural processes. This short paper presents and discusses a ...theoretical hypothesis for this organization in terms of feature sharedness. It is proposed that superordinate concepts involve a larger absolute number of exemplars that share a particular feature, thus making them more resistant to damage than basic level concepts (i.e. superordinate advantage). Simultaneously, in relative terms, features are less shared overall by superordinate members than by basic level members, which imply higher executive requirements and can conversely lead to superordinate deficits. This hypothesis is discussed in relation to behavioral data from semantic dementia and stroke aphasia patients and fMRI data from healthy subjects that support the role of feature sharedness in the hierarchical organization of semantic knowledge.
The environmental impact of electricity generation sources can be generically characterized by their use of natural resources, the thermal pollution they cause, and their emissions of chemical ...pollutants and radionuclides. Nuclear power plants generate concern regarding their radioactive emissions, which are often poorly understood. A presentation is made of the known data on the environmental impact of pre‐Gen III nuclear power plants during normal operation and as a consequence of severe accidents. The radiation doses received by the public and exposed workers as a consequence of nuclear power are compared with the ones because of natural radioactivity and medical applications. The characteristics of the new Gen III reactors which will bring significant improvements to the environmental impact of nuclear power generation are discussed in detail.
This article is categorized under:
Fossil Fuels > Climate and Environment
As one of the most important assets of the industry, it is crucial to fully characterise all failure modes showing potential to degrade the normal operation of induction motors (IMs). One of the ...failure modes which lacks detailed knowledge and proper diagnostic tools is the inter‐turn short‐circuit (SC) fault. Given the severity of such failure mode, it is pivotal to ensure that incipient fault symptoms are correctly identified, thus preventing critical damages to the IM. Unfortunately, the state‐of‐the‐art does not provide enough data to confirm whether the available diagnostic tools act out in due time to avoid permanent damage to the faulty IM. To evaluate the impacts of this failure mode in the temperature of the stator windings of an IM, this paper presents the results obtained from two alternative thermal models of the same IM, resorting to the lumped parameter thermal network method and to the finite elements method. The results confirm that diagnostic tools reported in the literature might not be effective, failing to correctly diagnose an inter‐turn SC fault and to warrant the lead time required to take actions suitable to prevent permanent damage to the IM.
▶ Soil CO2 emission was significantly higher in Slash-and-burn area when compared to Green. ▶ Slash-and-burn area presented higher spatial variations in the majority of the soil properties. ▶ The ...humification index relates better than others properties with soil CO2 emission.
Soil CO2 emission (FCO2) has been related to soil properties that are strongly influenced by agricultural management. The objective of this work was to study FCO2 and its relation to soil properties in adjacent areas cropped with sugarcane managed with Slash-and-burn (SB) and Green (G) harvest. FCO2 was significantly higher (p<0.01; 2.74μmolm−2s−1 in SB and 2.07μmolm−2s−1 in G) in SB. Total emission in the 70-day period after harvest was also higher in the SB plot (729gCO2m−2) when compared to the G (557gCO2m−2) plot. Organic matter content and carbon stock (0–25cm) were 13% and 20% higher in SB, respectively, when compared to G. Other soil properties that presented significant difference between plots were pH, available phosphorus, sum of bases, cation exchange capacity, texture, and humification index of soil organic matter. The SB plot presented higher spatial variations in the majority of the soil properties, including FCO2, when compared to the G plot. Principal component analysis sustains the distinction of two groups, G soil samples and SB soil samples, separately. Regression analysis was able to explain up to 75% and 45% of the FCO2 spatial variability in SB and G harvested areas, respectively, and indicates that the humification index of soil organic matter, and its interaction with soil bulk density, is an important factor not just to differentiate emissions in each plot. Linear correlation between humification and FCO2 in each management system shows a positive correlation (p<0.10) in the G area and negative correlation (p<0.05) in the SB area. In addition, the interaction between humification index and bulk density relates better than others properties with soil CO2 emission, with this property being the most important to understand the emission variability in the Slash-and-burn area.
Our understanding of the dynamics of ion collisional energy loss in a plasma is still not complete, in part due to the difficulty and lack of high-quality experimental measurements. These ...measurements are crucial to benchmark existing models. Here, we show that such a measurement is possible using high-flux proton beams accelerated by high intensity short pulse lasers, where there is a high number of particles in a picosecond pulse, which is ideal for measurements in quickly expanding plasmas. By reducing the energy bandwidth of the protons using a passive selector, we have made proton stopping measurements in partially ionized Argon and fully ionized Hydrogen plasmas with electron temperatures of hundreds of eV and densities in the range 10
-10
cm
. In the first case, we have observed, consistently with previous reports, enhanced stopping of protons when compared to stopping power in non-ionized gas. In the second case, we have observed for the first time the regime of reduced stopping, which is theoretically predicted in such hot and fully ionized plasma. The versatility of these tunable short-pulse laser based ion sources, where the ion type and energy can be changed at will, could open up the possibility for a variety of ion stopping power measurements in plasmas so long as they are well characterized in terms of temperature and density. In turn, these measurements will allow tests of the validity of existing theoretical models.
The inquiry on the nature of truth in language comprehension has a long history of opposite perspectives. These perspectives either consider that there are qualitative differences in the processing ...of true and false statements, or that these processes are fundamentally the same and only differ in quantitative terms. The present study evaluated the processing nature of true and false statements in terms of patterns of brain activity using event-related functional-Magnetic-Resonance-Imaging (
fMRI). We show that when true and false concept-feature statements are controlled for relation strength/ambiguity, their processing is associated to qualitatively different processes. Verifying true statements activates the left inferior parietal cortex and the caudate nucleus, a neural correlate compatible with an extended search and matching process for particular stored information. In contrast, verifying false statements activates the fronto-polar cortex and is compatible with a reasoning process of finding and evaluating a contradiction between the sentence information and stored knowledge.
To gain more knowledge of changes in main pulmonary artery flow and right ventricular mass and volumes in patients with pulmonary hypertension during epoprostenol therapy.
Eleven patients (9 women) ...were evaluated before the start of therapy and every 4 months thereafter. Right and left ventricular volumes and masses were measured by cine MRI. Flow was measured with MRI velocity quantification. At the same times, 6-min walking tests were performed. Right-heart catheterizations were performed at baseline and after 1 year.
Right ventricular mass in the patient group was significantly higher from that in a control group of healthy volunteers (95 ± 26 g vs 42 ± 10 g, p < 0.05 mean ± SD), whereas the stroke volume was lower (34 ± 11 mL vs 81 ± 11 mL, p < 0.05). The greatest improvement in right ventricular stroke volume (to 41 ± 11 mL, p < 0.05) took place in the first 4 months. During the 1-year follow-up, right ventricular end-diastolic volume and mass did not change, and mean pulmonary artery pressure remained nearly stable at 55 mm Hg at baseline and 53 mm Hg after 1 year. Pulmonary vascular resistance decreased by 12.5% (p = 0.06).
From these data we conclude that epoprostenol lowers pulmonary vascular resistance, leading to an increase in pulmonary artery flow. This increase in pulmonary artery flow corresponds well with the increase in 6-min walking distance and can be noninvasively monitored by MRI (flow quantification). Right ventricular dilatation and hypertrophy are not reversed by epoprostenol therapy, but do not progress either.
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