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51.
M.P. Seabra H. Paiva J.A. Labrincha V.M. Ferreira 《Construction and Building Materials》2009,23(2):1147-1153
Especially in rehabilitation works, the use of lime based mortars have been increasing due to the need of compatibility between the old and the new materials. The mortars fresh state properties are extremely important since determines the material workability and also have a great influence on its hardened state characteristics.In this work, the fresh state properties of aerial lime pastes and aerial lime based mortars were investigated. The torque variation with time and the mortar rheological parameters (relative yield stress and plastic viscosity) were obtained using a rheometer suitable for mortars. The correlation of rheological data with slump and relative density measurements was studied.The mortars workability is affected by several parameters, namely, the binder/aggregate and water/binder ratios, the kneading water content, the admixtures type and amount. The admixtures influence (type and amount) on the fresh state properties of aerial lime based mortars are discussed. The used admixtures were the most common ones for several mortars, such as a water-retaining agent, a plasticizer and an air-entraining agent. 相似文献
52.
Topological reconfiguration is an important tool for the planning and operation of electric power distribution systems. The amount of time that an algorithm spends to obtain an alternative topological status for the system is not a primary concern, as the main goals of distribution operation planning are the reduction of power losses, the enhancement of the voltage profile, and the increase of reliability levels. The utility can use multiple criteria regarding the observation of regulation policies and public awareness to drive the topological reconfiguration. Several researchers are looking for new optimization methods, as the complexity of this combinatorial issue is high in large systems and the classic optimization methods are failing to address the problem reasonably. Therefore, a new fuzzy multi-criteria decision making algorithm for the proper processing of the information sources available at the utilities in the context of distribution network reconfiguration is proposed. The algorithm is evaluated through the use of a proof-of-concept implementation in a set of case studies based on actual distribution systems. 相似文献
53.
Bruna Oliveira Paula Quinteiro Carla Caetano Helena Nadais Luís Arroja Eduardo Ferreira da Silva Manuel Senos Matias 《Water and Environment Journal》2013,27(1):99-106
The most common practice for disposal of dead bodies is inhumation in soil, which favours interactions with the surrounding environment and returns nutrients to the life cycle. However, when the burial ground is located where hydrogeological, geological and climatic conditions are not favourable to the process, contamination of soils and groundwater may occur, and decomposition may be inhibited, leading to social, economic and political problems. The most critical parameters when assessing the pollution potential of a burial ground are inhumation depth, geological formation, depth of the water table, density of inhumations, soil type and climate. Considering that, this paper presents an overview of the potential threat that cemeteries can pose, analysing and discussing the influence of the main variables causing environmental impacts and public health risks. 相似文献
54.
Paulo Santos Diogo Peixoto Inês Ferreira Ricardo Passos Pedro Pires Marco Simes Pedro Pouso-Ferreira Teresa Baptista Benjamín Costas 《International journal of molecular sciences》2022,23(3)
Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases. 相似文献
55.
Richard M. Gunner Rory P. Wilson Mark D. Holton Phil Hopkins Stephen H. Bell Nikki J. Marks Nigel C. Bennett Sam Ferreira Danny Govender Pauli Viljoen Angela Bruns O. Louis van Schalkwyk Mads F. Bertelsen Carlos M. Duarte Martin C. van Rooyen Craig J. Tambling Aoife Gppert Delmar Diesel D. Michael Scantlebury 《Journal of the Royal Society Interface》2022,19(186)
The combined use of global positioning system (GPS) technology and motion sensors within the discipline of movement ecology has increased over recent years. This is particularly the case for instrumented wildlife, with many studies now opting to record parameters at high (infra-second) sampling frequencies. However, the detail with which GPS loggers can elucidate fine-scale movement depends on the precision and accuracy of fixes, with accuracy being affected by signal reception. We hypothesized that animal behaviour was the main factor affecting fix inaccuracy, with inherent GPS positional noise (jitter) being most apparent during GPS fixes for non-moving locations, thereby producing disproportionate error during rest periods. A movement-verified filtering (MVF) protocol was constructed to compare GPS-derived speed data with dynamic body acceleration, to provide a computationally quick method for identifying genuine travelling movement. This method was tested on 11 free-ranging lions (Panthera leo) fitted with collar-mounted GPS units and tri-axial motion sensors recording at 1 and 40 Hz, respectively. The findings support the hypothesis and show that distance moved estimates were, on average, overestimated by greater than 80% prior to GPS screening. We present the conceptual and mathematical protocols for screening fix inaccuracy within high-resolution GPS datasets and demonstrate the importance that MVF has for avoiding inaccurate and biased estimates of movement. 相似文献
56.
The validation of a method for the simultaneous quantification of furanic compounds in coated deep-fried samples processed and handled as usually consumed is presented. The deep-fried food was grinded using a device that simulates the mastication, and immediately analysed by headspace solid phase microextraction coupled to gas chromatography-mass spectrometry. Parameters affecting the efficiency of HS-SPME procedure were selected by response surface methodology, using a 2(3) full-factorial central composite design. Optimal conditions were achieved using 2g of sample, 3g of NaCl and 40min of absorption time at 37°C. Consistency between predicted and experimented values was observed and quality parameters of the method were established. As a result, furan, 2-furfural, furfuryl alcohol and 2-pentylfuran were, for the first time, simultaneously detected and quantified (5.59, 0.27, 10.48 and 1.77μgg(-1) sample, respectively) in coated deep-fried fish, contributing to a better understanding of the amounts of these compounds in food. 相似文献
57.
Pinela J Barros L Dueñas M Carvalho AM Santos-Buelga C Ferreira IC 《Food chemistry》2012,135(3):1028-1035
The antioxidant activity and phytochemical composition (ascorbic acid, free sugars and phenolic compounds) of decoctions and infusions of wild and commercial samples of Tuberaria lignosa (Sweet) Samp. Aerial parts were evaluated and compared. Among wild samples, the effects of the drying method (freeze or shade-drying) on those parameters were studied. Infusion of the freeze-dried wild sample gave the highest levels of sugars, while infusion of shade-dried wild sample and decoction of the freeze-dried sample presented higher ascorbic acid and phenolic compounds content (including ellagitannins and flavonoids) than the other samples. The last two samples also revealed higher antioxidant activity, in some cases even higher than Trolox. Decoctions gave lower amounts of disaccharides than infusions, which seemed to be hydrolysed, increasing the content of monosaccharides. Commercial samples showed the lowest content in phenolic compounds, mainly in ellagitannins and flavonoids, and also the lowest antioxidant activity. This work gives scientific evidence to the traditional medicinal uses of wild Tuberaria lignosa, highlighting the interest of its decoctions and infusions as a source of bioactive compounds and functional beverages. 相似文献
58.
The presence of saliva in the oral environment is relevant for several essential health processes. However, the noncontrolled early saliva interaction with biomaterials manufactured for oral rehabilitation may generate alterations in the superficial properties causing negative biological outcomes. Therefore, the present review aimed to provide a compilation of all possible physical–chemical–biological changes caused by the early saliva interaction in dental implants and materials for oral regeneration. Dental implants, bone substitutes and membranes in dentistry possess different properties focused on improving the healing process when in contact with oral tissues. The early saliva interaction was shown to impair some positive features present in biomaterials related to quick cellular adhesion and proliferation, such as surface hydrophilicity, cellular viability and antibacterial properties. Moreover, biomaterials that interacted with contaminated saliva containing specific bacteria demonstrated favorable conditions for increased bacterial metabolism. Additionally, the quantity of investigations associating biomaterials with early saliva interaction is still scarce in the current literature and requires clarification to prevent clinical failures. Therefore, clinically, controlling saliva exposure to sites involving the application of biomaterials must be prioritized in order to reduce impairment in important biomaterial properties developed for rapid healing. 相似文献
59.
60.
Scientometrics - The theme related to the oil production in the Brazilian territory is not limited to the extraction means, distribution and use of this product, and involves political, cultural... 相似文献