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101.
Fungal strains were screened for lipase producing activities and 10 strains were classified as good producers. Aspergillus sp., Fusarium sp., and Penicillium sp. exhibited the highest activities when fermented in wheat bran (WB) and soybean bran (SB). No fungal growth was observed using sugarcane bagasse (CB). An experimental design was applied to incorporate CB into the fermentation process for lipase production by Aspergillus sp. and Penicillium sp., and to evaluate the best moisture content for the substrate. Strains studied achieved maximum lipase activities with 25% CB combined with 75% WB or SB at 40% moisture content. The highest lipase activities were observed for WB and SB, and for SB combined with CB using Aspergillus sp. Fermentation of 96 h was the optimum period for enzyme production.  相似文献   
102.
Whey proteins are widely used as nutritional and functional ingredients in formulated foods because they are relatively inexpensive, generally recognized as safe (GRAS) ingredient, and possess important biological, physical, and chemical functionalities. Denaturation and aggregation behavior of these proteins is of particular relevance toward manufacture of novel nanostructures with a number of potential uses. When these processes are properly engineered and controlled, whey proteins may be formed into nanohydrogels, nanofibrils, or nanotubes and be used as carrier of bioactive compounds. This review intends to discuss the latest understandings of nanoscale phenomena of whey protein denaturation and aggregation that may contribute for the design of protein nanostructures. Whey protein aggregation and gelation pathways under different processing and environmental conditions such as microwave heating, high voltage, and moderate electrical fields, high pressure, temperature, pH, and ionic strength were critically assessed. Moreover, several potential applications of nanohydrogels, nanofibrils, and nanotubes for controlled release of nutraceutical compounds (e.g. probiotics, vitamins, antioxidants, and peptides) were also included. Controlling the size of protein networks at nanoscale through application of different processing and environmental conditions can open perspectives for development of nanostructures with new or improved functionalities for incorporation and release of nutraceuticals in food matrices.  相似文献   
103.
A model was developed to simulate oxygen accumulation in space and time within cylindrical dynamic accumulation chambers that are used to measure oxygen transmission rate (OTR) of materials. The model is based on Fick's law of diffusion and was validated against actual OTR measurements of polymer film samples. Measured OTR values and thicknesses were inputted into the model and oxygen concentrations outputted by the model. OTRs determined from the output of the model was in close agreement to within 0.3–3% of the measured OTR. Oxygen concentration versus time curves generated from model output oxygen concentrations and experimentally measured oxygen concentrations for three actual films were also in agreement. The model was then used to simulate results from three hypothetical test films at varying chamber lengths in order to evaluate effects of accumulation chamber dimensions relative to films on resulting OTR measurements. A typical design scenario was used, where the oxygen sensor is mounted on the chamber wall opposite the sample film. Results demonstrate that dynamic accumulation OTR instrument designers have considerable flexibility in choosing accumulation chamber dimensions because deviations in OTR are only expected to occur at impractically extreme chamber lengths (>10 m) for the entire envelope of OTRs expected for typical packaging films. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
104.
The effect of the addition of a new functional fibre (high-amylose maize starch, HAMS, as a source of resistant starch), recently available in the market, on sensory characteristics and consumers' acceptability of milk puddings was studied. Milk puddings containing modified waxy maize starch and κ-carrageenan were produced with different HAMS concentrations (0, 1, 2, 3 and 4%). Higher HAMS concentration caused changes in the sensory characteristics of milk puddings. Particularly, sensory attributes such as some roughness, rough afterfeel and floury taste appeared. Besides, the addition of HAMS caused an increase in manual and oral thickness and a decrease in creaminess, melting, and sweetness. A HAMS enrichment level of 1.4% in this product was estimated as the maximum concentration that does not significantly modify consumers' overall acceptability. Using survival analysis the proportion of consumers who would buy milk desserts containing 1.4 % HAMS was estimated as 71%. Consumers more interested in consuming functional foods enriched with fibre were more tolerant to the sensory changes caused by the addition of HAMS to the milk puddings.  相似文献   
105.
Synthesis of a polyfluorene/poly(p‐phenylene vinylene) derivative, the Poly [(9,9′‐di‐hexylfluorenediylvinylene‐alt‐1,4‐phenylenevinylene)‐co‐((9,9′‐(3‐t‐butylpropanoate) fluorene‐1,4‐phenylene)] (LaPPS 42) was performed following Wittig and Suzuki routes. Polyfluorenes and derivatives have been used in electroluminescent devices, and the synthesis described here has the advantage in pave the way to get distinct structures having different emission spectra. An extensive study of its electrochemical, thermomechanical, optical, and structural properties was carried out, as well as its application in electroluminescent devices. Polymer light‐emitting diodes (PLEDs) and polymer light‐emitting electrochemical cells (PLECs) were built using LaPPS 42 as active layer, and their electric and optical characterizations confirm they have a potential as active element in electroluminescent devices. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42579.  相似文献   
106.
A 22 factorial design (two factors at two levels, in triplicate) was performed to investigate the influence of factors A (time of treatment, 15 and 30 days) and B (chia oil content in a supplemented diet, at 2.1 and 4.2 %) in three responses of interest referring to: (a) the incorporation of alpha‐linolenic acid (LNA) in lipids of Nile tilapia fillet; (b) the enhancement of n‐3 fatty acids; and (c) the decrease in the omega‐6/omega3 (n‐6/n‐3) ratio in fish. Factors A and B were significant in the three regression models obtained and the interaction AB was a significant contributor to the LNA and n‐6/n‐3 ratio. Analysis of variance suggested three significant and predictive mathematical models. Response surfaces analyses from designs indicated higher LNA and n‐3 contents and a lower n‐6/n‐3 ratio using both factors A and B in the higher levels (30 days of treatment and 4.2 % of chia oil in the diet for fish) chosen for this study.  相似文献   
107.
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   
108.
New design approaches can be observed in an increasing number of botanical gardens due to a desire to improve the effectiveness of environmental interpretation. This paper presents a review of these recent trends in the display of plants based on a search of botanical gardens around the world and on both theory and previous research findings that have focused on understanding people's experience in botanical gardens and other environmental interpretation settings. Four design strategies of plant display were identified, which are referred to here as familiar frames, icons, imitations and manipulations of nature. These typological categories represent recent design approaches useful for establishing stronger relationships between people, plants and associated environmental issues. Further, the potential of such displays as environmental interpretation tools is discussed based on how people perceive them.  相似文献   
109.
Dampness is an important degradation issue especially in old buildings and monumental heritage, particularly a rising one as the result of capillary movement of water in the lower sections of walls and other ground-supported structures by capillary action. There are several methods to treat this kind of dampness among which is the wall base hygro-regulated ventilation system an interesting solution for high thick walls with considerable heterogeneity.

A significant number of studies have been undertaken around this method which have been implemented and validated in several heritage buildings. Such achievement has led to the adoption of the HUMIVENT patent system which aims to increase evaporation through peripheral channels on the base of the ventilated walls. A pre-sizing design program was also created and was called HUMIVENT PREDIM.

This study aims to develop a set of auxiliary abacus for pre-sizing wall base ventilation systems. This approach aims to provide fast and expeditious systems sizing in the design and rehabilitation project offices. It allows an easy awareness in the several parameters that influence the wet front and the preliminary ventilation system design. It is a very useful tool for designers allowing them to obtain pre-sizing without extensive knowledge of the program and the associated parameters and with quick understanding of the drying process optimization. For better awareness of the abacus’ potentiality and use, an application example is provided thereof. It is concluded that the abacus can straightforwardly be used for sensitivity studies and for the selection of the best solution in each case.  相似文献   

110.
One of the earliest synthetic antimalarial drugs, quinacrine, was recently reported as interesting for the treatment of acute myeloid leukemia. Inspired by this and similar findings, we evaluated a set of quinacrine analogues against gastric (MKN‐28), colon (Caco‐2), and breast (MFC‐7) cancer cell lines and one normal human fibroblast cell line (HFF‐1). All the compounds, previously developed by us as dual‐stage antimalarial leads, displayed antiproliferative activity, and one of the set stood out as selective toward the gastric cancer cell line, MKN‐28. Interestingly, this compound was transported across an in vitro MKN‐28 model cell line in low amounts, and approximately 80 % was trapped inside those cells. Nuclear targeting of the same compound and its interactions with calf thymus DNA were assessed through combined fluorescence microscopy, spectroscopy, and calorimetry studies, which provided evidence for the compound's ability to reach the nucleus and to interact with DNA.  相似文献   
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