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161.
Jesús Gallardo Ana I. Molina Crescencio Bravo Miguel A. Redondo César A. Collazos 《Expert systems with applications》2011,38(2):1099-1118
One of the most important aspects of collaborative systems is the concept of awareness, which refers to the perception and knowledge of the group and its activities. Support for the design and automatic development of awareness mechanisms within collaborative systems is hard to find. Furthermore, awareness conceptualizations are usually partial and differ greatly between the proposals of different authors. In response to these problems, we propose an awareness ontology that conceptualizes some of the most important aspects of awareness in a specific kind of system: collaborative systems for carrying out modeling activities. The awareness ontology brings together and extends a series of ontologies we have developed in the past. The ontology is prepared to better meet the specific implementation needs of a model-driven development approach. In order to validate the usefulness of this ontology, we relate its concepts to the awareness dimensions set out in Gutwin and Greenberg’s framework, and we apply the ontology to two systems presently in use. 相似文献
162.
Predicting moisture loss is important when developing a model for vacuum frying, because one of its objectives is to remove food moisture. A diffusion model was considered to describe moisture transfer during vacuum frying. Granny Smith apple slabs were processed at 16.6, 13.3, and 8 kPa and between 80 and 120°C. Moisture diffusivity was determined, obtaining a close fit between the model and the experimental data. Diffusivity increased with temperature and decreased when pressure increased. A direct proportionality between heat and mass transfer was observed. Temperature influence was interpreted by the Arrhenius relationship and there was no observed effect of pressure on the activation energy. 相似文献
163.
J. Oh M. Harper F. Giallongo D.M. Bravo E.H. Wall A.N. Hristov 《Journal of dairy science》2017,100(3):1888-1901
The objective of this experiment was to investigate the effects of rumen-protected Capsicum oleoresin (RPC) supplementation on feed intake, milk yield and composition, nutrient utilization, fecal microbial ecology, and responses to a glucose tolerance test in lactating dairy cows. Nine multiparous Holstein cows were used in a replicated 3 × 3 Latin square design balanced for residual effects with three 28-d periods. Each period consisted of 14 d for adaptation and 14 d for data collection and sampling. Treatments were 0 (control), 100, and 200 mg of RPC/cow per day. They were mixed with a small portion of the total mixed ration and top-dressed. Glucose tolerance test was conducted once during each experimental period by intravenous administration of glucose at a rate of 0.3 g/kg of body weight. Dry matter intake was not affected by RPC. Milk yield tended to increase for RPC treatments compared to the control. Feed efficiency was linearly increased by RPC supplementation. Concentrations of fat, true protein, and lactose in milk were not affected by RPC. Apparent total-tract digestibility of dry matter, organic matter, and crude protein was linearly increased, and fecal nitrogen excretion was linearly decreased by RPC supplementation. Rumen-protected Capsicum oleoresin did not affect the composition of fecal bacteria. Glucose concentration in serum was not affected by RPC supplementation post glucose challenge. However, compared to the control, RPC decreased serum insulin concentration at 5, 10, and 40 min post glucose challenge. The area under the insulin concentration curve was also decreased 25% by RPC. Concentration of nonesterified fatty acids and β-hydroxybutyrate in serum were not affected by RPC following glucose administration. In this study, RPC tended to increase milk production and increased feed efficiency in dairy cows. In addition, RPC decreased serum insulin concentration during the glucose tolerance test, but glucose concentration was not affected by treatment. 相似文献
164.
Juan Morales‐Corona José A. López‐Barrera Alejandro Avila‐Ortega Guillermo J. Cruz María‐Guadalupe Olayo Mauricio Ortega‐López Miguelina Vasquez‐Ortega Humberto Vazquez Roberto Olayo 《应用聚合物科学杂志》2012,123(2):1120-1124
This work presents the synthesis by plasma and characterization of luminescent polymer thin films of dibenzothiophene (DBT) by plasma polymerization. The DBT is solid at room conditions and was sublimated and introduced to the plasma reactor to produce the chemical reactions with the vapors. The results indicated the production of polymers with benzene and thiophene rings in the structure as well as methylene groups. The polymer structure was studied by Fourier transform infrared spectroscopy and 13C‐CPMAS. The thermal analysis showed a residual mass of 60% at 800°C, which suggests a great thermal resilience in the polymer. The critical superficial tension was calculated with a Zisman plot and was 25 mN/m. The polymer has a fluorescent green emission between 400 and 660 nm and an orange emission between 660 and 850 nm. This effect can be a consequence of the electronic distribution along the structure in aliphatic and aromatic segments with benzene and thiophene rings. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
165.
Plants produce an extensive array of organic compounds derived from secondary metabolism that may be useful in animal nutrition because of their chemical makeup. These plant-derived bioactive compounds, also referred to as phytonutrients (PN) or phytobiotics, have been shown to express antimicrobial activities against a wide range of bacteria, yeast, and fungi and have been investigated as rumen modifiers in ruminant nutrition. Studies have reported that PN may inhibit deamination of AA and methanogenesis in the rumen and shift fermentation toward propionate and butyrate. Most of the experiments, however, have been conducted in vitro, and responses have been highly variable and inconsistent in animal experiments. In addition, some studies have reported that PN had positive effects on productivity, although rumen fermentation was not affected. Other than antimicrobial effects in the gut, PN are known to bind specific receptors expressed in neurons, intestines, and other cells and exhibit related physiological effects in nonruminants. The receptor-mediated effects include immune responses, oxidative stress, and insulin secretion and activity. Some PN, due to their phenolic nature, are likely less susceptible to microbial degradation in the rumen and may exhibit activities postruminally, similar to their mode of action in nonruminant species. This opens a new area of research in ruminants, including effects of PN on the animal's immune system, postruminal nutrient use, and animal physiology. Although limited, studies with ruminants provide first evidence of PN's regulatory effects on the host responses. For example, PN were reported to regulate immune cells related to adaptive and innate immunity in challenged or nonchallenged dairy cows. Supplementation of PN reduced oxidative stress by decreasing lipid peroxidation and increasing endogenous antioxidants in ruminants. Additionally, insulin secretion and sensitivity were reportedly regulated by PN in dairy cows. The regulatory effects of PN on immunity may be beneficial for immune suppression and inflammation in dairy cows. In addition, PN could positively affect energy partitioning for milk production through their effects on insulin secretion and sensitivity. Further research is needed to elucidate the effect and mode of action of PN on immune function and animal energetics. 相似文献
166.
Carlos Eduardo Molina-Guerrero Guadalupe de la Rosa Hiram Castillo-Michel Arturo Sánchez Concepción García-Castañeda Angélica Hernández-Rayas Idania Valdez-Vazquez Santiago Suarez-Vázquez 《化学工程与技术》2018,41(7):1350-1350
The changes occurring during the depolymerization of lignocellulosic biomasses are not yet fully understood. Synchrotron micro‐Fourier transform infrared (µ‐FTIR), Raman spectroscopy (RS), X‐ray diffraction (XRD), and X‐ray fluorescence (XRF) were applied for better characterization of wheat straw fibers during a continuous pretreatment process in terms of conditioning (C), extrusion (E), steam explosion (SE), and enzymatic hydrolysis (EH). µ‐FTIR revealed functional groups as phenylpropanoid polymers, ethers, and aliphatic alcohol. RS detected acetoacetate, methyl and phenol groups after SE. The crystallinity index and silica content were also determined. 相似文献
167.
Vermont P. Dia Sarah Frankland-Searby Francisco Laso del Hierro Guadalupe Garcia Elvira Gonzalez de Mejia 《Food chemistry》2013
Lunasin is a 43-amino acid naturally occurring chemopreventive peptide with demonstrated anti-cancer and anti-inflammatory properties. The objectives of this study were to determine the effect of temperature on the secondary structure of lunasin, to develop a method of isolating lunasin from human plasma using an ion-exchange microspin column and to quantify the amount of lunasin using an optimized enzyme-linked immunosorbent assay. Lunasin was purified using a combination of ion-exchange chromatography, ultrafiltration and gel filtration chromatography. Circular dichroism showed that increased in temperature from 25 to 100 °C resulted in changes on the secondary structure of lunasin and its capability to interact with rabbit polyclonal antibody. Enzyme linked immunosorbent assay showed that lunasin rabbit polyclonal antibody has a titer of 250 and a specific activity of 0.05 mL/μg. A linear response was detected between 16 to 48 ng lunasin per mL (y = 0.03x − 0.38, R2 = 0.96). The use of diethylaminoethyl microspin column to isolate spiked lunasin in human plasma showed that most lunasin (37.8–46.5%) bound to the column eluted with Tris–HCl buffer, pH 7.5 with a yield up to 76.6%. In conclusion, lunasin can be isolated from human plasma by a simple DEAE microspin column technique and can be quantified using a validated and optimized immunoassay procedure. This method can be used directly to quantify lunasin from plasma in different human and animal studies aiming to determine its bioavailability. 相似文献
168.
Monica Bravo 《History of Photography》2018,42(1):61-77
An optogram is an image fixed on the retina by a biological, photochemical process. In the late nineteenth century, it was widely believed that optograms could be excised from dead bodies to procure their final visions. Optograms were most frequently compared to photographs, so that the retina of the eye was likened to the sensitive plate in a camera. Just as photography became capable of superseding human vision in the 1870s, optograms discursively came to light as latent photographs, making photography the original for preconscious sight. These historical inversions of primacy challenge our conceptions of the relation between nature and culture in photography, with the cultural invention preceding the natural discovery of optography. This article examines how an incidental, speculative, and ultimately forgotten discovery in the physical sciences was deployed rhetorically to reinforce personal or disciplinary beliefs about what photography was and what it could do, in realms ranging from physiological laboratories to science fiction, from police departments to courtrooms. Analysis of optographic discourse indicates that the true value of photography in the late nineteenth century was not primarily in the photograph’s relation to its indexical referent, but in the possibility that it might grant access to seeing as another living being. 相似文献
169.
Maria T. Morales Guadalupe Luna R. Aparicio 《European Food Research and Technology》2000,211(3):222-228
Winey-vinegary sensory defect was evaluated in virgin olive oil samples from a sensory and chemical point of view. Qualitative
and quantitative differences were found in the profile of volatiles of extra-virgin olive oil samples without sensory defects
and samples with high intensities of winey-vinegary sensory attribute. Several volatile compounds were found to be correlated
to winey-vinegary sensory defect in virgin olive oils, acetic acid and ethyl acetate having correlation coefficients of 0.98
and 0.94 respectively. A synthetic sample was obtained with the sensory characteristics of the winey defect. Samples with
low values of winey sensory defect were also studied and the evaluation of the presence of the defect using the content of
four volatile compounds only was demonstrated.
Received: 5 August 1999 / Revised version: 22 October 1999 相似文献
170.
Jesús Calviño Juan Bravo Lucía Martínez Beatriz Millán José R Pulpeiro 《Hemodialysis international. International Symposium on Home Hemodialysis》2013,17(3):455-457
Uneventful central venous catheterization for hemodialysis patients may not always result in a correct tip position. A case of inadvertent cannulation of the azygos vein is described. Radiographic features for its early recognition are emphasized and mechanisms related with azygos unintended catheterization are discussed. 相似文献