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101.
The main aim of this research was to introduce a green and clean method of increasing the nutritional quality while preserving the quality of extruded maize snacks. This was achieved by addition of soybean flour (5%, 10%, 15% and 20%, w/w) as a source of plant protein, fibre and bioactive compounds and changing the feed moisture content. Extruded samples were produced using a single-screw extruder. Increasing the soybean flour and feed moisture content resulted in reduced specific mechanical energy of the extruder and consequently several changes in physicochemical properties of the snacks including higher moisture content, lower expansion and volume, reduced crispiness, reduction in L-and a-values but an increase in b-value and formation of more wrinkly and thicker air bubbles cell walls as observed under scanning electron microscope. The addition of <20% soybean flour and feed moisture content resulted in snacks with improved nutritional value and physical properties.  相似文献   
102.
A simple, inexpensive and efficient three phase hollow fibre liquid phase microextraction (HF-LPME) technique combined with HPLC was used for the simultaneous determination of flavonoids in Echinophora platyloba DC. and Mentha piperita. Different factors affecting the HF-LPME procedure were investigated and optimised. The optimised extraction conditions were as follows: 1-octanol as an organic solvent, pHdonor = 2, pHacceptor = 9.75, stirring rate of 1000 rpm, extraction time of 80 min, without addition of salt. Under these conditions, the enrichment factors ranged between 146 and 311. The values of intra and inter-day relative standard deviations (RSD) were in the range of 3.18–6.00% and 7.25–11.00%, respectively. The limits of detection (LODs) ranged between 0.5 and 7.0 ng mL−1. Among the investigated flavonoids quercetin was found in E. platyloba DC. and luteolin was found in M. piperita. Concentration of quercetin and luteolin was 0.015 and 0.025 mg g−1 respectively.  相似文献   
103.
In a cement factory, a rotary kiln is the most complex component and it plays a key role in the quality and quantity of the final product. This system involves complex nonlinear dynamic equations that have not been completely worked out yet. In conventional modeling procedures, a large number of the involved parameters are crossed out and an approximation model is presented instead. Therefore, the performance of the obtained model is very important and an inaccurate model may cause many problems in the design of a controller. This study presents a Takagi-Sugeno (TS)-type fuzzy system called a wavelet projection fuzzy inference system (WPFIS) in which a dimension reduction section is used at the input stage of the fuzzy system. In order to clarify the structure of the extracted features, structural learning with forgetting (SLF) based on Minkowski norms is proposed. In addition, gradient descent (GD) was used as a training algorithm. The results show that the proposed method has higher performance in comparison with conventional models. The data collected from Saveh White Cement Company were used in our simulations.  相似文献   
104.
This paper presents a distributed deployment algorithm for a network of autonomous agents. The main goal is to perform a coverage task when the sensor effectiveness of each agent varies during the mission. It is also assumed that the agents are subject to communication delays induced by communication faults. To improve the overall performance and guarantee the collision avoidance, the guaranteed multiplicatively-weighted Voronoi (GMW-Voronoi) diagram is introduced. A distributed coverage control is then provided to drive agents in such a way that the coverage performance function is minimized over the regions assigned to agents. The effectiveness of the proposed algorithm is evaluated by simulations.  相似文献   
105.
Pattern Analysis and Applications - In this paper, a 2D representation of a video clip called video spatiotemporal map (VSTM) is presented. VSTM is a compact representation of a video clip which...  相似文献   
106.
A routine monitoring for subacute ruminal acidosis (SARA) on the individual level could support the minimization of economic losses and the ensuring of animal welfare in dairy cows. The objectives of this study were (1) to develop a SARA risk score (SRS) by combining information from different data acquisition systems to generate an integrative indicator trait, (2) the investigation of associations of the SRS with feed analysis data, blood characteristics, performance data, and milk composition, including the fatty acid (FA) profile, (3) the development of a milk mid-infrared (MIR) spectra-based prediction equation for this novel reference trait SRS, and (4) its application to an external data set consisting of MIR data of test day records to investigate the association between the MIR-based predictions of the SRS and the milk FA profile. The primary data set, which was used for the objectives (1) to (3), consisted of data collected from 10 commercial farms with a total of 100 Holstein cows in early lactation. The data comprised barn climate parameters, pH and temperature logging from intrareticular measurement boluses, as well as jaw movement and locomotion behavior recordings of noseband-sensor halters and pedometers. Further sampling and data collection included feed samples, blood samples, milk performance, and milk samples, whereof the latter were used to get the milk MIR spectra and to estimate the main milk components, the milk FA profile, and the lactoferrin content. Because all measurements were characterized by different temporal resolutions, the data preparation consisted of an aggregation into values on a daily basis and merging it into one data set. For the development of the SRS, a total of 7 traits were selected, which were derived from measurements of pH and temperature in the reticulum, chewing behavior, and milk yield. After adjustment for fixed effects and standardization, these 7 traits were combined into the SRS using a linear combination and directional weights based on current knowledge derived from literature studies. The secondary data set was used for objective (4) and consisted of test day records of the entire herds, including performance data, milk MIR spectra and MIR-predicted FA. At farm level, it could be shown that diets with higher proportions of concentrated feed resulted in both lower daily mean pH and higher SRS values. On the individual level, an increased SRS could be associated with a modified FA profile (e.g., lower levels of short- and medium-chain FA, higher levels of C17:0, odd- and branched-chain FA). Furthermore, a milk MIR-based partial least squares regression model with a moderate predictability was established for the SRS. This work provides the basis for the development of routine SARA monitoring and demonstrates the high potential of milk composition-based assessment of the health status of lactating cows.  相似文献   
107.
108.
Biofilms are detrimental in many industrial and biomedical applications and prevention of biofilm formation has been a prime challenge for decades. Biofilms consist of communities of adhering bacteria, supported and protected by extracellular‐polymeric‐substances (EPS), the so‐called “house of biofilm organisms”. EPS consists of water, proteins, polysaccharides and extracellular‐DNA (eDNA). eDNA, being the longest molecule in EPS, connects the different EPS components and therewith holds an adhering biofilm together. eDNA is associated with bacterial cell surfaces by specific and non‐specific mechanisms, mediating binding of other biopolymers in EPS. eDNA therewith assists in facilitating adhesion, aggregation and maintenance of biofilm structure. Here, a new method is described to prevent biofilm formation on surfaces by applying a DNase I enzyme coating to polymethylmethacrylate, using dopamine as an intermediate. The intermediate coupling layer and final DNase I coating are characterized by water‐contact‐angle measurements and X‐ray photoelectron‐spectroscopy. The DNase I coating strongly reduces adhesion of Staphylococcus aureus (95%) and Pseudomonas aeruginosa (99%) and prevents biofilm formation up to 14 h, without affecting mammalian cell adhesion and proliferation. Also agarose‐gel‐electrophoresis indicates loss of enzyme activity between 8 and 24 h. This duration however, is similar to many local antibiotic‐delivery devices, which makes it an ideal coating for biomaterial implants and devices, known to fail due to biofilm formation with disastrous consequences for patients and high costs to the healthcare system. With threatening increases in antibiotic resistance, the DNase I coating may provide a timely, potent new approach to biofilm prevention on biomaterial implants and devices.  相似文献   
109.
This paper presents low-power carbon nanotube field-effect transistor (CNTFET)-based quaternary logic circuits. The proposed quaternary circuits are designed based on the CNTFET unique properties, such as the same carrier mobility for N- and P-type devices and also providing desirable threshold voltages by adopting proper diameters for the nanotubes. In addition, no paths exist between supply and ground rails in the steady states of the proposed designs, which eliminates the ON state static current and also the stacking technique is utilised in order to significantly reduce the leakage currents. The results of the simulations, conducted using Synopsys HSPICE with the standard 32 nm CNTFET technology, confirm the significantly lower power consumption, higher energy efficiency and lower sensitivity to process variation of the proposed designs compared to the state-of-the-art quaternary logic circuits. The proposed quaternary logic circuits have on average 92, 99 and 91% less total power, static power and PDP, respectively, compared with the most low-power and energy-efficient CNTFET-based quaternary logic circuits, recently presented in the literature.  相似文献   
110.
The prevention of unpleasant boar taint is the main reason for castration of male piglets. For animal welfare reasons, castration is announced to be banned in the European Community. This study aimed to investigate whether androstenone, skatole and indole in backfat of boars may be reduced by different scalding technologies. To discriminate ante and post mortem effects, carcasses were sampled before and after scalding in two abattoirs using either horizontal (TANK) or vertical (TUNNEL) scalding. Backfat samples were analysed using gas chromatography (androstenone) and liquid chromatography (skatole, indole). Neither TANK nor TUNNEL scalding did significantly reduce malodorous compounds. Skatole and androstenone in backfat obtained after scalding averaged 112 ± 123 ng/g and 1196 ± 885 ng/g melted fat, respectively; significant differences between abattoirs were observed for skatole. Increased skatole levels were tentatively assigned to longer transport duration. Concluding from recent consumer research and subsequent application of suggested sensory rejection thresholds for androstenone (2000 ng/g) and skatole (150 ng/g), nearly 30% of the carcasses may be unacceptably tainted.  相似文献   
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