61 research outputs found

    Using K-Means Algorithm for Description Analysis of Text in RSS News Format

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    This article shows the use of different techniques for the extraction of information through text mining. Through this implementation, the performance of each of the techniques in the dataset analysis process can be identified, which allows the reader to recommend the most appropriate technique for the processing of this type of data. This article shows the implementation of the K-means algorithm to determine the location of the news described in RSS format and the results of this type of grouping through a descriptive analysis of the resulting clusters

    Paraoxonase-1 is related to inflammation, fibrosis and PPAR delta in experimental liver disease

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    <p>Abstract</p> <p>Background</p> <p>Paraoxonase-1 (PON1) is an antioxidant enzyme synthesized by the liver. It protects against liver impairment and attenuates the production of the pro-inflammatory monocyte chemoattractant protein-1 (MCP-1). We investigated the relationships between hepatic PON1 and MCP-1 expression in rats with liver disease and explored the possible molecular mechanisms involved.</p> <p>Methods</p> <p>CCl<sub>4 </sub>was administered for up to 12 weeks to induce liver damage. Serum and hepatic levels of PON1 and MCP-1, their gene and protein expression, nuclear transcription factors, and histological and biochemical markers of liver impairment were measured.</p> <p>Results</p> <p>High levels of PON1 and MCP-1 expression were observed at 12<sup>th </sup>week in the hepatocytes surrounding the fibrous septa and inflammatory areas. CCl<sub>4</sub>-administered rats had an increased hepatic PON1 concentration that was related to decreased gene transcription and inhibited protein degradation. Decreased PON1 gene transcription was associated with PPARδ expression. These changes were accompanied by increased hepatic MCP-1 concentration and gene expression. There were significant direct relationships between hepatic PON1 and MCP-1 concentrations (P = 0.005) and between PON1 and the amount of activated stellate cells (P = 0.001).</p> <p>Conclusion</p> <p>Our results from this experimental model suggest a hepato-protective role for PON1 against inflammation, fibrosis and liver disease mediated by MCP-1.</p

    Protein Kinase Cδ Stimulates Proteasome-Dependent Degradation of C/EBPα during Apoptosis Induction of Leukemic Cells

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    BACKGROUND:The precise regulation and maintenance of balance between cell proliferation, differentiation and death in metazoan are critical for tissue homeostasis. CCAAT/enhancer-binding protein alpha (C/EBPalpha) has been implicated as a key regulator of differentiation and proliferation in various cell types. Here we investigated the potential dynamic change and role of C/EBPalpha protein during apoptosis induction. METHODOLOGY/PRINCIPAL FINDINGS:Upon onset of apoptosis induced by various kinds of inducers such as NSC606985, etoposide and others, C/EBPalpha expression presented a profound down-regulation in leukemic cell lines and primary cells via induction of protein degradation and inhibition of transcription, as assessed respectively by cycloheximide inhibition test, real-time quantitative RT-PCR and luciferase reporter assay. Applying chemical inhibition, forced expression of dominant negative mutant and catalytic fragment (CF) of protein kinase Cdelta (PKCdelta), which was proteolytically activated during apoptosis induction tested, we showed that the active PKCdelta protein contributed to the increased degradation of C/EBPalpha protein. Three specific proteasome inhibitors antagonized C/EBPalpha degradation during apoptosis induction. More importantly, ectopic expression of PKCdelta-CF stimulated the ubiquitination of C/EBPalpha protein, while the chemical inhibition of PKCdelta action significantly inhibited the enhanced ubiquitination of C/EBPalpha protein under NSC606985 treatment. Additionally, silencing of C/EBPalpha expression by small interfering RNAs enhanced, while inducible expression of C/EBPalpha inhibited NSC606985/etoposide-induced apoptosis in leukemic cells. CONCLUSIONS/SIGNIFICANCE:These observations indicate that the activation of PKCdelta upon apoptosis results in the increased proteasome-dependent degradation of C/EBPalpha, which partially contributes to PKCdelta-mediated apoptosis

    Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

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    The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

    A query processing framework for efficient network resource utilization in shared sensor networks

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    202212 bcchAccepted ManuscriptRGCOthersOthers: Germany/Hong Kong Joint Research Scheme 2019/20 G-PolyU504/19Publishe

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    Not AvailableA 60-day experimental trial was conducted to investigate the effect of different dosages of potassium supple- mentation on Spinacia oleracea L. and Pangasianodon hypophthalmus in an aquaponic system. The system con- sisted of 168 l rectangular fish tanks (0.78 × 0.54 × 0.40 m) with 100 l water volume stocked with P. hypophthalmus at 2.8 kg m-3 and Nutrient Film Technique (NFT) hydroponics with spinach at 28 plants m-2. Four dosages of potassium viz., 90, 120, 150, and 180 mg l-1 were assigned as T1, T2, T3, and T4 and compared with control C (0 mg l-1) to determine the most efficient potassium dosage for the aquaponic system. The physico- chemical parameters and nutrient dynamics were within the permissible range with no marked variation be- tween the control and treatments. The spinach was harvested twice. The first harvest before potassium sup- plementation showed no significant difference. In the second harvest, the potassium supplementation had a significant (P < 0.05) effect on the yield of spinach with the highest yield obtained in T4 (280.07 ± 2.26 g) followed by T3 (277.57 ± 3.02 g), T2 (265.07 ± 4.61 g), T1 (256.80 ± 4.79 g) and C (217.83 ± 4.20 g). The yield showed no significant difference in T4 and T3, and T2 and T1. The mean body weight of fish at harvest was insignificant (P > 0.05) and followed the order: C (33.23 ± 0.52 g)>T1 (33.07 ± 0.45 g)>T2 (32.94 ± 0.40 g)> T3 (32.23 ± 0.37 g)>T4 (32.15 ± 0.35 g). The plant analysis revealed that potassium supplementation triggered the nutrient synergism resulting in higher nitrogen, potassium, phosphorus, iron, and sulfur content in T4 fol- lowed by T3, T2, T1, and C. The evaluation of the physiological response of P. hypophthalmus showed higher plasma glucose in T4. Considering the water quality parameters, fish growth, physiological response, spinach yield, and nutrient content, a dose of 150 mg l-1 K+ (T3) could be recommended as an optimum potassium dosage for P. hypophthalmus-Spinacia oleracea L. aquaponic system.Not Availabl

    Adaptive crossover memetic differential harmony search for optimizing document clustering

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    An Adaptive Crossover Memetic Differential Harmony Search (ACMDHS) method was developed for optimizing document clustering in this paper. Due to the complexity of the documents available today, the allocation of the centroid of the document clusters and finding the optimum clusters in the search space are more complex to deal with. One of the possible enhancements on the document clustering is the use of Harmony Search (HS) algorithm to optimize the search. As HS is highly dependent on its control parameters, a differential version of HS was introduced. In the modified version of HS, the Band Width parameter (BW) has been replaced by another pitch adjustment technique due to the sensitivity of the BW parameter. Thus, the Differential Evolution (DE) mutation was used instead. In this paper the DE crossover was also used with the Differential HS for further search space exploitation, the produced global search is named Crossover DHS (CDHS). Moreover, DE crossover (Cr) and mutation (F) probabilities are dynamically tuned through generations. The Memetic optimization was used to enhance the local search capability of CDHS. The proposed ACMDHS was compared to other document clustering techniques using HS, DHS, and K-means methods. It was also compared to its other two variants which are the Memetic DHS (MDHS) and the Crossover Memetic Differential Harmony Search (CMDHS). Moreover, two state-of-the-art clustering methods were also considered in comparisons, the Chaotic Gradient Artificial Bee Colony (CGABC) and the Differential Evolution Memetic Clustering (DEMC). From the experimental results, it was shown that CMDHS variant (the non-adaptive version of ACMDHS) and ACMDHS were highly competitive while both CMDHS and ACMDHS were superior to all other methods

    A Survey of Methods for the Construction of an Intrusion Detection System

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    International audienceCybercrimes committed using computer networks lead to billions of dollars lose, the illegal access into computer system, stealing valuable data and destroying organization networks which in turn affect the cyber resources. Because of the expansion of attacks or threats on the networks infrastructure, which is nothing but can be consider as an illegitimate intrusion, based on the machine learning methodology, the intrusion detection system (IDS) can consider as one of the most used cyber security mechanisms, thus to detect the promiscuous activities against sensitive and private data. In this paper our target is to provide a guide lines for researchers and developers discussing the IDS construction phases and their latest techniques, we will clarify the most applied data sources employed in the proposition of a model that will be built for the purpose of creating an intelligent detection system. Furthermore, this survey presents the most commons and latest methods employed and used for designing an IDS based on the data mining techniques and discusses the artifacts removal by summarizing the advantages with the disadvantages of the currents methods and addressing the last novel steps into this field of research
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