256 research outputs found
Parameter identification for piecewise-affine fuzzy models in noisy environment
AbstractIn this paper the problem of identifying a fuzzy model from noisy data is addressed. The piecewise-affine fuzzy model structure is used as non-linear prototype for a multi–input, single–output unknown system. The consequents of the fuzzy model are identified from noisy data which are collected from experiments on the real system. The identification procedure is formulated within the Frisch scheme, well established for linear systems, which is extended so that it applies to piecewise-affine, constrained models
Genetic abnormalities in pancreatic cancer
The incidence and mortality of pancreatic adenocarcinoma are nearly coincident having a five-year survival of less than 5%. Enormous advances have been made in our knowledge of the molecular alterations commonly present in ductal cancer and other pancreatic malignancies. One significant outcome of these studies is the recognition that common ductal cancers have a distinct molecular fingerprint compared to other nonductal or endocrine tumors. Ductal carcinomas typically show alteration of K-ras, p53, p16(INK4), DPC4 and FHIT, while other pancreatic tumor types show different aberrations. Among those tumors arising from the exocrine pancreas, only ampullary cancers have a molecular fingerprint that may involve some of the same genes most frequently altered in common ductal cancers. Significant molecular heterogeneity also exists among pancreatic endocrine tumors. Nonfunctioning pancreatic endocrine tumors have frequent mutations in MEN-1 and may be further subdivided into two clinically relevant subgroups based on the amount of chromosomal alterations. The present review will provide a brief overview of the genetic alterations that have been identified in the various subgroups of pancreatic tumors. These results have important implications for the development of genetic screening tests, early diagnosis, and prognostic genetic markers
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What an original app! : a study on the novelty of software products
Innovation in software is important to both members of the public and the software industry, and involves developing software that is both useful and novel. While novelty has attracted significant interest in relation to physical products, it is not so well studied in the context of software products. In this paper, we aim to help develop our understanding of novelty in software by investigating which kinds of software products are seen as more or less novel; what factors may contribute most to perceptions of novelty in software, and whether members of the public and those involved in software development think in the same ways about these things. Through a study consisting of 3 stages, we identify examples of software products that are seen as original, at time of writing, by both software specialists and members of the public, and also two key factors–use of software in a new context, and use of a new underlying technology, which appear to contribute strongly to perceptions of novelty in software. We briefly discuss the implications of our findings and directions for further work
Fecal concentrations of cortisol, testosterone, and progesterone in cotton-top tamarins hosted in different zoological parks: Relationship among physiological data, environmental conditions and behavioral patterns
The aim of this investigation was to study the welfare of three captive groups of cotton-top tamarins housed in different zoological parks. Ethological observations were conducted over one year. In addition, fecal samples were collected and the concentrations of glucocorticoids, androgens, and progestagens were measured. Within each group, no significant differences in fecal cortisol concentrations were found between subjects. The fecal concentrations of testosterone and progesterone significantly differed depending on the sex and the age of the animals. A significant association was found among hormone concentrations, exhibit dimension, and group composition. A highly significant correlation was uncovered between all hormones considered and the space available for each subject. Significant differences in behavioral patterns were observed among groups, including social-individual, affiliative-aggressive, and anogenital-suprapubic scent marking. Correlations between hormone measurements and behaviors were detected. In conclusion, this study confirmed the associations between some behaviors exhibited by these nonhuman primates and both cortisol and testosterone; these data also highlight the role played by progesterone in these behaviors
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On the novelty of software products
The identification of the key factors that make a tangible product creative has been the focus of significant research in the area of design. However, the same effort for software products is almost non-existent. With the ever-increasing importance of software applications in day-to-day life, such endeavour becomes more necessary. In this paper we report on preliminary results that build on our understanding of how we evaluate the creativity of tangible products, to identify key criteria that can be used in assessing the creativity of intangible software products. We argue that this provides a basis for designers to work together with software developers in pushing the boundaries of software innovation
Endogenous coenzyme Q content and exogenous bioavailability in D. melanogaster
Development and aging significantly impact the cellular levels of Coenzyme Q (CoQ), which is associated with both pathological and physiological conditions. Aim of this study was to describe the CoQ status throughout the lifetime of Drosophila melanogaster, a well-established model in aging studies. CoQ9 and CoQ10 distribution was analysed across different body segments and various life stages in both male and female flies. The results indicate that CoQ(9) is the predominant isoform in every phase of flies' life cycle, with the highest concentrations observed in the thorax. We noted distinct trends in CoQ distribution during aging, which varied according to sex and body segments (head, thorax, and abdomen). Supplementation with two concentrations of CoQ(9) and CoQ(10) (15 mu M and 75 mu M) for 2 weeks induced a segment- and sex-specific CoQ uptake. Although 75 mu M CoQ(10) was more effective in modulating the CoQ status, lifelong treatment with this concentration did not affect the longevity of the flies
Hairy garlic (Allium subhirsutum) from Sicily (Italy): LC-DAD-MSn analysis of secondary metabolites and in vitro biological properties
Allium subhirsutum, known as hairy garlic, is a bulbous plant widespread in the Mediterranean area and locally used as a food and spice. In the present study, the chemical profile of the ethanolic extracts from bulbs (BE) and aerial parts (APE) were analyzed by HPLC-ESI-MSn, and antioxidant properties were evaluated by DPPH, ABTS and TEAC assays. The traditional use in the diet, and the well documented biological activity of Allium species suggest a potential as a new nutraceutical. For this reason, the potential usefulness of this food can be considered in the treatment and prevention of degenerative Alzheimer disease. For this reason, acetylcholinesterase inhibitory property was investigated. Furthermore, due to the observed presence of sulfur-containing and phenolic constituents, the cytotoxicity on tumor cells line was investigated. Results revealed significant AChE inhibitory activity for BE and APE. Both extracts exhibited also moderate antioxidant properties in the in vitro assays. Finally, limited cytotoxic activity was observed towards Human colon carcinoma and adenocarcinoma cell line, with differences between the individual parts tested. HPLC-ESI-MSn analysis showed that hairy garlic is a good source of sulphur compounds, flavonoids and phenylpropanoids derivatives, thus being a valid alternative to the common garlic (A. sativum). This work opens new opportunities for the application of A. subhirsutum as a health-promoting food
Antioxidant and Anti-Inflammatory Profiles of Spent Coffee Ground Extracts for the Treatment of Neurodegeneration
Spent coffee grounds (SCGs), waste products of coffee beverage production, are rich in organic compounds such as phenols. Different studies have demonstrated phenol beneficial effects in counteracting neurodegenerative diseases. These diseases are associated with oxidative stress and neuroinflammation, which initiates the degeneration of neurons by overactivating microglia. Unfortunately, to date, there are no pharmacological therapies to treat these pathologies. The aim of this study was to evaluate the phenolic content of 4 different SCG extracts and their ability to counteract oxidative stress and neuroinflammation. Caffeine and 5-O-caffeoylquinic acid were the most abundant compounds in all extracts, followed by 3-O-caffeoylquinic acid and 3,5-O-dicaffeoylquinic acid. The four extracts demonstrated a different ability to counteract oxidative stress and neuroinflammation in vitro. In particular, the methanol extract was the most effective in protecting neuron-like SH-SY5Y cells against H2O2-induced oxidative stress by upregulating endogenous antioxidant enzymes such as thioredoxin reductase, heme oxygenase 1, NADPH quinone oxidoreductase, and glutathione reductase. The water extract was the most effective in counteracting lipopolysaccharide-induced neuroinflammation in microglial BV-2 cells by strongly reducing the expression of proinflammatory mediators through the modulation of the TLR4/NF-kappa B pathway. On these bases, SCG extracts could represent valuable nutraceutical sources for the treatment of neurodegeneratio
Pterostilbene Promotes Mean Lifespan in Both Male and Female Drosophila Melanogaster Modulating Different Proteins in the Two Sexes
Aging is a multifactorial phenomenon characterized by degenerative processes closely connected to oxidative damage and chronic inflammation. Recently, many studies have shown that natural bioactive compounds are useful in delaying the aging process. In this work, we studied the effects of an in vivo supplementation of the stilbenoid pterostilbene on lifespan extension in Drosophila melanogaster. We found that the average lifespan of flies of both sexes was increased by pterostilbene supplementation with a higher effect in females. The expression of longevity related genes (Sir2, Foxo, and Notch) was increased in both sexes but with different patterns. Pterostilbene counteracted oxidative stress induced by ethanol and paraquat and up-regulated the antioxidant enzymes Ho e Trxr-1 in male but not in female flies. On the other hand, pterostilbene decreased the inflammatory mediators dome and egr only in female flies. Proteomic analysis revealed that pterostilbene modulates 113 proteins in male flies and only 9 in females. Only one of these proteins was modulated by pterostilbene in both sexes: vacuolar H[+] ATPase 68 kDa subunit 2 (Vha68-2) that was strongly down-regulated. These findings suggest a potential role of pterostilbene in increasing lifespan both in male and female flies by mechanisms that seem to be different in the two sexes, highlighting the need to conduct nutraceutical supplementation studies on males and females separately in order to give more reliable results
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