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101.
Paiva Pedro Yuri Arbs Moreno Camila Castro Smith-Miles Kate Valeriano Maria Gabriela Lorena Ana Carolina 《Machine Learning》2022,111(8):3085-3123
Machine Learning - Machine Learning studies often involve a series of computational experiments in which the predictive performance of multiple models are compared across one or more datasets. The... 相似文献
102.
De la Torre C Illa I Faulkner G Soria L Robles-Cedeño R Dominguez-Perles R De Luna N Gallardo E 《Proteomics. Clinical applications》2009,3(4):486-497
The muscular dystrophies are a large and heterogeneous group of neuromuscular disorders that can be classified according to the mode of inheritance, the clinical phenotype and the molecular defect. To better understand the pathological mechanisms of dysferlin myopathy we compared the protein-expression pattern in the muscle biopsies of six patients with this disease with six patients with limb girdle muscular dystrophy 2A, five with facioscapulohumeral dystrophy and six normal control subjects. To investigate differences in the expression levels of skeletal muscle proteins we used 2-DE and MS. Western blot or immunohistochemistry confirmed relevant results. The study showed specific increase expression of proteins involved in fast-to-slow fiber type conversion (ankyrin repeat protein 2), type I predominance (phosphorylated forms of slow troponin T), sarcomere stabilization (actinin-associated LIM protein), protein ubiquitination (TRIM 72) and skeletal muscle differentiation (Rho-GDP-dissociation inhibitor ly-GDI) in dysferlin myopathy. As anticipated, we also found differential expression of proteins common to all the muscular dystrophies studied. This comparative proteomic analysis suggests that in dysferlin myopathy (i) the type I fiber predominance is an active process of fiber type conversion rather than a selective loss of type II fibers and (ii) the dysregulation of proteins involved in muscle differentiation further confirms the role of dysferlin in this process. 相似文献
103.
Moliner Carolina; Martínez-Tur Vicente; Peiró José M.; Ramos José; Cropanzano Russell 《Canadian Metallurgical Quarterly》2005,12(2):99
Relationships between organizational justice and well-being are traditionally investigated at the individual level. This article extends previous efforts by testing such relationships at the work-unit level. Three corridors of influence were examined. First, the level (work units' average scores) of justice is related to the level of burnout. Second, justice climate strength (level of agreement among work-unit members) moderates the predictability of the level of burnout. Third, justice strength is related to burnout strength. The authors interviewed 324 contact employees from 108 work units in 59 service organizations. Findings showed the predominance of interactional justice over distributive and procedural justice in all 3 corridors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Santiago P. Aubourg Silvia Testi Minia Sanxuás Carolina Gil & Jorge Barros-Velázquez 《International Journal of Food Science & Technology》2009,44(8):1595-1601
A combined refrigeration system consisting of ozone and flow ice was evaluated for the sacrifice, cooling and chilled storage of continental trout. The batch processed in ozonised flow ice exhibited significant ( P < 0.05) reductions (0.97 and 1.51 log CFU cm−2 ) in skin aerobes and psychrotrophs on days 6 and 9, respectively, and significant ( P < 0.05) reductions (0.94 log CFU g−1 and 0.96 log CFU g−1 ) in aerobes, and proteolytic bacteria in muscle on day 13. A significant ( P < 0.05) inhibition of TMA-N formation after 9 days was also observed, with an average reduction of 28.4% along the storage period, Slight reductions in autolytic breakdown mechanisms were also observed in the ozonised batch, a maximum reduction of 14.82% being reached on day 13. The microbial and biochemical changes were well correlated with the sensory evaluation, which revealed relevant differences between the batches on day 13 and a shelf life extension of the ozonised batch up to day 16. 相似文献
105.
KE Toomey TA Peterman LW Dicker AA Zaidi JE Wroten J Carolina 《Canadian Metallurgical Quarterly》1998,25(6):310-316
OBJECTIVE: Determine the cost and effectiveness of partner notification for human immunodeficiency virus (HIV) infection. METHODS: Persons testing HIV positive in three areas were randomly assigned one of four approaches to partner notification. Analysis plans changed because disease intervention specialists notified many partners from the patient referral group. We dropped the patient referral group and combined the others to assess the cost and effectiveness of provider referral. RESULTS: The 1,070 patients reported 8,633 partners. Of those 1,035 were located via record search or in person. A previous positive test was reported by 248 partners. Of the 787 others, 560 were tested: 438 were HIV negative and 122 were newly identified as HIV positive. The intervention specialist's time totaled 197 minutes per index patient. The cost of the intervention specialist's time, travel, and overhead was $268,425: $251 per index patient, $427 per partner notified, or $2,200 per new HIV infection identified. No demographic characteristic of the index patient strongly predicted the likelihood of finding an infected partner. CONCLUSION: We could not compare the effectiveness of different partner notification approaches because of frequent crossover between randomized groups. The cost of partner notification can be compared with other approaches to acquired immunodeficiency syndrome prevention, but the benefits are not easily measured. We do not know the number of HIV cases prevented or the value of fulfilling the ethical obligation to warn partners of a potential threat to their health. 相似文献
106.
Gallic acid degradation in aqueous solutions by UV/H2O2 treatment, Fenton's reagent and the photo-Fenton system 总被引:1,自引:0,他引:1
Gallic acid (3,4,5-trihydroxybenzoic acid) is a major pollutant present in the wastewater generated in the boiling cork process, as well as in other wastewaters from food manufacturing industries. Its decay in aqueous solutions has been studied by the action of several oxidation systems: monochromatic UV radiation alone and combined with hydrogen peroxide, Fenton's reagent and the combination Fenton's reagent with UV radiation (photo-Fenton system). The influence of the pH is discussed and the quantum yields are determined in the UV radiation system. Also, the influence of operating variables (initial concentrations of H2O2 and Fe(II), and pH) is established in the Fenton's reaction. The apparent pseudo-first-order rate constants are evaluated in all the experiments conducted in order to compare the efficiency of each one of the processes. Increases in the degradation levels of gallic acid are obtained in the combined processes in relation to the single UV radiation system, due to reactions of the very reactive OH*. These improvements are determined in every process by calculating the partial contribution to the overall decomposition rate of the radical pathways. For the oxidant concentrations applied, the most effective process in removing gallic acid was found to be the photo-Fenton system. The rate constant for the reaction of gallic acid with OH was also determined by means of a competition kinetics model, being its value 11.0+/-0.1 x 10(9)l mol(-1)s(-1). 相似文献
107.
Nowadays there is an increasing number of recombinant enzymes made available to industry. Before replacing the use of natural enzymes with their cognate recombinant counterparts, one important issue to address is their actual equivalence. For a given recombinant proteolytic enzyme, its equivalence can be investigated by comparing its cleavage specificity with that obtained from the natural enzyme. This is mostly done by analyzing the fragments (i.e., peptidic map) attained after enzymatic digestion of a given protein used as substrate. The peptidic maps obtained are typically characterized using separation techniques together with MS and MS/MS systems. However, these procedures are known to be difficult and labor-intensive. In this work, the combined use of a theoretical model that relates electrophoretic behavior of peptides to their sequence together with capillary electrophoresis-mass spectrometry (CE-MS) is proposed to characterize in a very fast and simple way the cleavage specificity of new recombinant enzymes. Namely, the effectiveness of this procedure is demonstrated by analyzing in few minutes the fragments obtained from a protein hydrolysated using recombinant and natural pepsin A. The usefulness of this strategy is further corroborated by CE-MS/MS. The proposed procedure is applicable in many other proteomic studies involving CE-MS of peptides. 相似文献
108.
Abstract: Samples of unblanched (fresh), stannous chloride-treated, or blanched jalapeño peppers were measured for real-time generation of lipoxygenase-derived volatiles during 10 min after tissue disruption. Volatiles were also measured before and after 1.5, 2.5, 3, 6, and 9 mo of frozen storage at −15 °C. The concentration of all lipoxygenase-derived compounds was significantly higher in unblanched jalapeño peppers compared to enzyme inhibited peppers. The maximum concentration of (Z)-3-hexenal, (E)-2-hexenal, and hexanal was detected at about 1.2, 1.5, and 1.5 min after tissue disruption, respectively. A decrease in (Z)-3-hexenal and an increase in dimethyl sulfide and methylbutanal occurred in blanched compared to stannous chloride-treated peppers due to heat. Frozen storage resulted in no major changes in the lipoxygenase-derived volatiles of whole and pureed blanched peppers after 9 mo. However, in whole unblanched peppers a gradual decrease of (Z)-3-hexenal, (E)-2-hexenal, hexanal, hexenol, and hexanol was observed over time; whereas in pureed unblanched peppers these compounds increased, reached maximum concentration, and then decreased. Similarly, the minor volatiles 2-pentenal, 1-penten-3-one, (E)-2-heptenal, (E)-2-octenal, and (E)-2-nonenal showed an initial increase followed by a decline in both whole and pureed unblanched peppers. Tissue disruption increased generation and degradation rates during frozen storage. The compounds (E,Z)-2,6-nonadienal, n-propyl aldehyde, 2-isobutyl-3-methoxypyrazine, and a mixture of terpenes decreased in unblanched and blanched frozen samples, while nonanal and methylbutanal increased only in unblanched samples. Practical Application: Data obtained in this study contribute to the understanding of the dynamics of lipoxygenase-derived volatile formation upon tissue disruption of jalapeño pepper. In addition, it contributes to generate knowledge on the effect of processing techniques, namely blanching and frozen storage, on the volatile profile of these peppers. This knowledge has applications in the manufacturing, product development, and quality control areas of the food industry as useful information to help in the designing and monitoring of processes aimed to obtain products with specific aroma characteristics. For instance, maximum levels of “fresh” and “green” aroma compounds are achieved rapidly during the first few minutes after pepper tissue is disrupted. The inhibition of enzyme activity shortly after this may help to maximize concentration of these aroma notes in the product. Frozen storage produces enzymatic and chemical changes in the volatile profile of unblanched peppers. The aroma profile of blanched peppers is more stable under frozen conditions, with a lower total volatile concentration. 相似文献
109.
Caroline D. Capitani Ana Carolina L. Carvalho Diogo P. Rivelli Silvia B. M. Barros Inar A. Castro 《European Journal of Lipid Science and Technology》2009,111(11):1090-1099
The antioxidant activity of natural and synthetic compounds was evaluated using five in vitro methods: ferric reducing/antioxidant power (FRAP), 2,2‐diphenyl‐1‐picrylhydradzyl (DPPH), oxygen radical absorption capacity (ORAC), oxidation of an aqueous dispersion of linoleic acid accelerated by azo‐initiators (LAOX), and oxidation of a meat homogenate submitted to a thermal treatment (TBARS). All results were expressed as Trolox equivalents. The application of multivariate statistical techniques suggested that the phenolic compounds (caffeic acid, carnosic acid, genistein and resveratrol), beyond their high antioxidant activity measured by the DPPH, FRAP and TBARS methods, showed the highest ability to react with the radicals in the ORAC methodology, compared to the other compounds evaluated in this study (ascorbic acid, erythorbate, tocopherol, BHT, Trolox, tryptophan, citric acid, EDTA, glutathione, lecithin, methionine and tyrosine). This property was significantly correlated with the number of phenolic rings and catecholic structure present in the molecule. Based on a multivariate analysis, it is possible to select compounds from different clusters and explore their antioxidant activity interactions in food products. 相似文献
110.
Federico Perez Carolina Nayme Ruera Emanuel Miculan Paula Carasi Fernando Gabriel Chirdo 《International journal of molecular sciences》2021,22(14)
The small intestine has a high rate of cell turnover under homeostatic conditions, and this increases further in response to infection or damage. Epithelial cells mostly die by apoptosis, but recent studies indicate that this may also involve pro-inflammatory pathways of programmed cell death, such as pyroptosis and necroptosis. Celiac disease (CD), the most prevalent immune-based enteropathy, is caused by loss of oral tolerance to peptides derived from wheat, rye, and barley in genetically predisposed individuals. Although cytotoxic cells and gluten-specific CD4+ Th1 cells are the central players in the pathology, inflammatory pathways induced by cell death may participate in driving and sustaining the disease through the release of alarmins. In this review, we summarize the recent literature addressing the role of programmed cell death pathways in the small intestine, describing how these mechanisms may contribute to CD and discussing their potential implications. 相似文献