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91.
92.
This work presents a new adsorption technique where the adsorbent (powdered activated carbon-PAC) is in the form of suspended flocs formed with water-soluble polymer flocculants. Thus, the adsorption of a typical dye, methylene blue (MB), was studied onto polyacrylamide flocs of PAC (PACF) in a fluidized bed reactor. The technique is based on the fact that the adsorption capacity of PAC does not decrease after flocculation because the adsorbed polymer occupies only a few surface sites, in the form of trains, loops, and tails. Moreover, the adsorption was found to proceed through a rapid mass transfer of MB to the adsorbing PAC flocs, in the same extent as onto PAC. Because of the rapid settling characteristics of the aggregates formed, the two phase separations, loaded PAC and solution, become easier. Thus, the technique offers the advantages of conducting simultaneously both adsorption and solid/liquid separation all in one single stage. Results obtained showed that high MB removal values can be attained in a fluidized bed reactor (>90%) and that PACF presents a much higher adsorption capacity (breakthrough points) than granulated activated carbon (GAC) in the same adsorbing bed. It is believed that this technique highly broadens the potential of the use of powdered activated carbon or other similar ultrafine adsorbents.  相似文献   
93.
The total solids required for yogurt preparation were obtained by soy milk microfiltration and ultrafiltration. Inulin was incorporated at the level of 20–70 g/L, and the soy milk containing inulin was fermented using conventional microorganisms. The chemical, physical and sensory properties of the products were evaluated. The membrane concentration of soy proteins leads to yogurts with an increase of 59 g/L of proteins and 15 g/L of vegetable fats, reducing ash and anti-nutrients content. The clot had high stability and protein concentration generated a buffer effect smoothing the acidity and the flavor obtained is more agreeable. In addition, the proteins were concentrated without thermal treatment. As the inulin content increased, creaminess and viscosity increased as well. The products prepared presented nice smell, flavor and color, being the sample with higher global acceptability the yogurt with 50 g/L of inulin (P < 0.05).  相似文献   
94.
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   
95.
The aim of this study is to evaluate the ability of physical training in the maintenance of muscle strength in rats with HFD (high-fat diet) after OVX (ovariectomy). Eighty Wistar rats are at eight weeks of age and weight 200 g which divided into 8 groups (n = 10) and treated for 12 weeks: GA: OVX + ND (normal diet), GB: OVX + ND + training, GC: sham + ND, GD: sham + ND + training, GE: OVX + HFD, GF: OVX + HFD + training, GG: sham + HFD and GH: sham + HFD + training. HFD consists of standard ration for rats with addition of 30% lipids. In training groups, physical training five training/week was conducted on a treadmill with adaptation period of three weeks up to 18 m/s for one hour, training were performed for 12 weeks. The sedentary animals remained in individual box. To analyze the effects of training and diet, tensile strength tests of the gastrocnemius muscles were conducted: the speed of 0.1 mm/min. Analysis of variance was performed to compare groups. The mean (SD) obtained for the maximum load (N) were: GA 57.77 (6.89), GB 62.74 (5.07), GC 49.45 (6.06), GD 59.42 (5.26) and GE 55.58 (4.72), GF 62.50 (4.56), GG 58.35 (4.54) and GH 56.67 (5.87), respectively. There were no differences for maximum load between surgeries (p = 0.004) and between treatments (p = 0.000). Differences were found also for the relationship surgery diet treatment (p = 0.007). For the variable stiffness (N/mm), there were not statistically significant differences: GA 5.03 (0.72), GB 5.08 (1.09), GC 5.17 (0.53), GD 5.35 (0.80), GE 5.52 (1.20), GF 5.36 (1.07), GG 4.83 (1.03) and GH 5.40 (0.73). For the toughness (N/mm), there were differences between treatments (p = 0.010) and the ratio diet treatment (p = 0.024): GA 455.00 (107.21), GB 541.96 (126.80), GC 394.97 (84.67), GD 566.90 (157.07); GE 424.63 (113.03), GF 478.07 (106.03); GG 517.44 (98.65?  相似文献   
96.
Plant-derived products and their extracted compounds have been used in folk medicine since early times. Zimbro or common juniper (Juniperus communis) is traditionally used to treat renal suppression, acute and chronic cystitis, bladder catarrh, albuminuria, leucorrhea, and amenorrhea. These uses are mainly attributed to its bioactive composition, which is very rich in phenolics, terpenoids, organic acids, alkaloids, and volatile compounds. In the last few years, several studies have analyzed the huge potential of this evergreen shrub, describing a wide range of activities with relevance in different biomedical discipline areas, namely antimicrobial potential against human pathogens and foodborne microorganisms, notorious antioxidant and anti-inflammatory activities, antidiabetic, antihypercholesterolemic and antihyperlipidemic effects, and neuroprotective action, as well as antiproliferative ability against cancer cells and the ability to activate inductive hepato-, renal- and gastroprotective mechanisms. Owing to these promising activities, extracts and bioactive compounds of juniper could be useful for the development of new pharmacological applications in the treatment of several acute and chronic human diseases.  相似文献   
97.
Putrescine (Put) is the starting point of the polyamines (PAs) pathway and the most common PA in higher plants. It is synthesized by two main pathways (from ornithine and arginine), but recently a third pathway from citrulline was reported in sesame plants. There is strong evidence that Put may play a crucial role not only in plant growth and development but also in the tolerance responses to the major stresses affecting crop production. The main strategies to investigate the involvement of PA in plant systems are based on the application of competitive inhibitors, exogenous PAs treatments, and the most efficient approaches based on mutant and transgenic plants. Thus, in this article, the recent advances in understanding the role of this metabolite in plant growth promotion and protection against abiotic and biotic stresses will be discussed to provide an overview for future research.  相似文献   
98.
99.
Neural Computing and Applications - Artificial neural networks have been proposed in medical research as an alternative to some regression models such as the generalized linear models, being the...  相似文献   
100.

Nowadays, the stability and the safe cover and closure of soft tailings has become one of the most challenging topics in geotechnical and environmental engineering. For appropriate analysis and modelling, geotechnical properties of tailings should be well defined. Due to low strength, viscous nature and poor trafficability, as well as due to the specific geometrical properties of fine particles and pore water chemistry in tailings, different test methods and their modification and improvements must be used for valid and reliable characterisation of tailings. This paper analyses and compares the results of different field test methods, piezocone penetration test (CPTu), flat dilatometer test (DMT) and field vane test (FVT), performed on the red gypsum sludge and complementary laboratory tests. CPTu and DMT measurements were evaluated using procedures developed for soils and the obtained mechanical properties were compared with those measured in the laboratory. The significant distinctions between different test methods and different empirical correlations were analysed taking into account differences in index properties of soils and the red gypsum sludge. Based on analysis, some modifications of conventional empirical correlations were proposed for field tests results interpretation and sludge characterisation. The obtained data also show the advantages and limitations of some conventional methods and prove the need for further development in that field of geotechnical investigation.

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