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Katsalirou E.,Technological Educational Institute of the Ionian Islands | Deng S.,Oklahoma State University | Nofziger D.L.,Oklahoma State University | Gerakis A.,Technological Educational Institute of the Ionian Islands | Fuhlendorf S.D.,Oklahoma State University
European Journal of Soil Biology | Year: 2010

Management of soil ecosystems requires assessment of key soil physicochemical and microbial properties and the spatial scale over which they operate. The objectives were to determine the spatial structure of microbial biomass and activity and related soil properties, and to identify spatial relationships of these properties in prairie soils under different management histories. Soil were sampled along a transect at 0.2 m intervals in each of five long-term treatments, namely, undisturbed, cattle grazed at two intensities, and cultivated with either wheat (Triticum aestivum L.) or cotton (Gossypium hirsutum L.). Contents of organic carbon (Corg), dissolved organic C (DOC), soluble nitrogen (Nsol), and microbial biomass C (Cmic) and N (Nmic) as well as dehydrogenase activity (DH) in 70 samples were evaluated. Results showed that long-term soil management altered the spatial structure and dependence of Corg and microbial biomass and activity. Cultivation has contributed to high nugget variance for Corg, Cmic, Nmic and DH which interfered with detection of spatial structure at the sampling scale used. Contents of Corg were spatially connected to microbial biomass and activity and to DOC in the uncultivated but not in the cultivated soils, indicating that various factors affected by management may operate at different spatial scales. © 2010 Elsevier Masson SAS.


Katsalirou E.,Technological Educational Institute of the Ionian Islands | Deng S.,Oklahoma State University | Nofziger D.L.,Oklahoma State University | Gerakis A.,Technological Educational Institute of the Ionian Islands
European Journal of Soil Biology | Year: 2010

Changes in soil microbial and biochemical properties in response to management practices reflect changes in the functional capacity of soil ecosystems. The objectives were to evaluate effects of long-term management practices on different soil organic C and N pools and activities of glycoside hydrolases, including α- and β-glucosidases, α- and β-galactosidases, cellulase, and invertase, in semiarid prairie soils. Soils were sampled from five long-term management systems including: undisturbed, abandoned from cultivation, moderately grazed, heavily grazed, and cultivated with winter wheat (Triticum aestivum L.). Activities of C-transforming enzymes were sensitive in discriminating soil ecosystems under various land uses and can be used as indicators for detecting impact of soil management practices on the soil capacity to cycle C. Long-term cultivation (more than 30 yr) decreased total organic C and N, microbial biomass, and activities of C-transforming enzymes, and led to development of a microbial community with enhanced metabolic activity. Grazing, especially at moderate intensity, did not lessen soil capacity to support microbial life and cycle C. The intermediate status of the chemical, microbial, and biochemical properties in the abandoned from cultivation soils suggested that through secondary succession the soil ecosystem is restoring its capacity to sequester C and support microbial life. © 2010 Elsevier Masson SAS.


Megalovasilis P.,Technological Educational Institute of the Ionian Islands | Papastergios G.,Aristotle University of Thessaloniki | Filippidis A.,Aristotle University of Thessaloniki
Environmental Monitoring and Assessment | Year: 2013

The Kozani-Ptolemais-Amyntaio basin constitutes the principal coal field of Greece. Approximately 50 % of the total power production of Greece is generated by five power stations operating in the area. Lignite samples, together with the corresponding fly ash and bottom ash were collected, over a period of 3 months, from the power plant of Amyntaio and analyzed for their content in 16 trace elements. The results indicate that Y, Nb, U, Rb, Zr, Ni, Pb, Ba, Zn, Sr, Cu, and Th demonstrate an organic affinity during the combustion of lignite, while V has an inorganic affinity. Three elements (Co, Cr, and Sc) show an intermediate affinity. © 2012 Springer Science+Business Media Dordrecht.


Alepis E.,University of Piraeus | Stathopoulou I.-O.,University of Piraeus | Virvou M.,University of Piraeus | Tsihrintzis G.A.,University of Piraeus | Kabassi K.,Technological Educational Institute of the Ionian Islands
Proceedings - International Conference on Tools with Artificial Intelligence, ICTAI | Year: 2010

Towards building a multimodal affect recognition system, we have built a facial expression recognition system and a audio-lingual affect recognition system. In this paper, we present and discuss the development and evaluation process of the two subsystems, concerning the recognition of emotions from audio-lingual and visual-facial modalities. Many researchers agree that these modalities are complementary to each other and that the combination of the two can improve the accuracy in affective user models. Therefore in this paper we present a combination of two modes using multi-criteria decision making theories. The resulted system takes advantage of the strengths of each mode and is more accurate in emotion recognition. © 2010 IEEE.


Kabassi K.,Technological Educational Institute of the Ionian Islands | Virvou M.,University of Piraeus
IEEE Transactions on Human-Machine Systems | Year: 2015

This research investigates the novel combination of multicriteria decision-making theories with a cognitive theory called human plausible reasoning (HPR) to provide personalized assistance via graphical user interfaces (GUIs). A GUI called intelligent file manipulator (IFM) helps with organizing computer file storage. The system reasons about user actions, goals, plans, and possible errors and offers automatic assistance in case of a problematic situation. Three multicriteria decision-making theories [simple additive weighting, multiattribute utility theory, and data envelopment analysis] were adapted, implemented, and combined with HPR, in turn. This process resulted in three different versions of IFM that were evaluated. The protocols of 30 users of different levels of expertise were provided to the system with each of the versions and to ten human experts. The responses of the experts and the different versions of the system were compared. The evaluation revealed that decision-making theories can increase control in an intelligent user interface. They can be combined with a cognitive theory like HPR. There was 66-81% compatibility of the different systems' responses to the proposals of the majority of experts. All decision-making theories were better in simulating the human experts' reasoning when there was unanimity of the human experts' opinion. In such cases, there was 68-84% compatibility of the different systems' responses to the experts' proposals. This research supports that HPR could successfully be completed by a multicriteria decision-making theory, and such combination can be effectively used for providing personalized help in GUIs. © 2013 IEEE.


James E.A.,Benaroya Research Institute | Moustakas A.K.,Technological Educational Institute of the Ionian Islands | Bui J.,Benaroya Research Institute | Papadopoulos G.K.,Epirus Institute of Technology | And 3 more authors.
Arthritis and Rheumatism | Year: 2010

Objective. HLA-DRB1*1001 (DR1001) is a shared epitope allele associated with rheumatoid arthritis (RA). The present study was undertaken to assess the capacity of DR1001 to accommodate citrulline in its binding pockets and to identify citrullinated T cell epitopes derived from joint-associated proteins. Methods. The binding of peptide derivatives containing citrulline, arginine, and other amino acid substitutions was measured. A prediction algorithm was developed to identify arginine-containing sequences from joint-associated proteins that preferentially bind to DR1001 upon citrullination. Unmodified and citrullinated versions of these sequences were synthesized and were utilized to stimulate CD4+ T cells from healthy subjects and RA patients. Responses were measured by class II major histocompatibility complex tetramer staining and confirmed by isolating CD4+ T cell clones. Results. DR1001 accepted citrulline, but not arginine, in 3 of its anchoring pockets. The prediction algorithm identified sequences that preferentially bound to DR1001 with arginine replaced by citrulline. Three of these sequences elicited CD4+ T cell responses. T cell clones specific for these sequences proliferated only in response to citrullinated peptides. Conclusion. Conversion of arginine to citrulline generates "altered-self" peptides that can be bound and presented by DR1001. Responses to these peptides implicate the corresponding proteins (fibrinogen α, fibrinogen β, and cartilage intermediate-layer protein) as relevant antigens. The finding of preferential responses to citrullinated sequences suggests that altered peptide binding affinity due to this posttranslational modification may be an important factor in the initiation or progression of RA. As such, measuring responsiveness to these peptides may be useful for immunologic monitoring. © 2010, American College of Rheumatology.


Behrens M.,Mayo Medical School | Papadopoulos G.K.,Epirus Institute of Technology | Moustakas A.,Technological Educational Institute of the Ionian Islands | Smart M.,Mayo Medical School | And 3 more authors.
Arthritis and Rheumatism | Year: 2011

Objective Certain HLA class II alleles are associated with susceptibility to the development of arthritis. However, the development of arthritis in some persons carrying non-rheumatoid arthritis (RA)-associated alleles remains unexplained. An individual who is heterozygous for the DQA1 and DQB1 genes can express the DQ molecule in cis or trans heterodimers. In a cis heterodimer, the α-chain interacts with the β-chain coded by the same chromosome, while in a trans heterodimer it interacts with the β-chain on the other chromosome. In this study, we used a humanized mouse model of arthritis in an attempt to determine whether a trans heterodimer of 2 nonassociated alleles, DQB1*0601 and DQB1*0604, can predispose to arthritis. Methods DQB1*0601 and*0604 occur in linkage with DQA1*0103 and*0102, respectively. To understand the role of trans heterodimers, we generated DQB1*0604/DQA1*0103-transgenic mice lacking endogenous HLA class II molecules. Results Severe arthritis developed in the DQB1*0604/A1*0103-trangenic mice, and an antigen-specific response was generated in vitro. DQB1*0604/DQA1*0103 presented type II collagen-derived peptides that were not presented by the arthritis-resistant DQB1*0601 allele, suggesting that trans heterodimer molecules between 2 DQB1 and DQA1 molecules may result in the presentation of unique antigens and susceptibility to the development of arthritis. Molecular modeling of type II collagen peptides showed that DQB1*0604/DQA1*0103 shares a p4 pocket with the arthritis-susceptible DQB1*0302 allele, suggesting a critical role of the p4 and p9 pockets in susceptibility to arthritis. Conclusion These results provide a possible explanation for the parental inheritance of nonsusceptibility alleles in some patients with RA and a mechanism by which they can predispose to the development of arthritis. Copyright © 2011 by the American College of Rheumatology.


Giotis C.,Technological Educational Institute of the Ionian Islands | Markellou E.,Benaki Phytopathological Institute | Theodoropoulou A.,Northumbria University | Kostoulas G.,Technological Educational Institute of the Ionian Islands | And 2 more authors.
Organic Agriculture | Year: 2012

An experiment was conducted in both 2008 and 2009 to develop and evaluate strategies for the control of cucumber powdery mildew caused by Podosphaera xanthii. Effects of biological control agents (BCAs) Ampelomyces quisqualis and Pythium oligandrum and plant defence elicitors Milsana® VP 2002 (a plant extract of Reynoutria sachalinensis) and chitosan (derived from chitin) alone and in combination on disease incidence and fruit yield of two cucumber cultivars were investigated. As the cultivars Gloria and Palmera differed in their tolerance to powdery mildew it was possible to test if the use of tolerant cultivars could maximise any beneficial effects of the treatments. In both cultivars in both years, the elicitor Milsana® VP 2002 reduced the disease incidence and fruit yield was similar to that from plants treated with the chemosynthetic fungicide treatments. Whilst foliar application of the other elicitor chitosan significantly reduced powdery mildew, it was less effective than Milsana® VP 2002. BCAs A. quisqualis and P. oligandrum were less effective than the elicitors Milsana® VP 2002 and chitosan and fruit yield was similar to untreated control plants. There was no synergistic or additive effects on disease control or fruit yield detected with any combinations. Disease tolerance of cultivars significantly affected disease incidence. However, the more susceptible cultivar Palmera outyielded the tolerant one (Gloria) despite greater infection. © 2012 Springer Science & Business Media BV.


Maravelakis E.,Technological Educational Institute of Crete | Konstantaras A.,Technological Educational Institute of Crete | Kabassi K.,Technological Educational Institute of the Ionian Islands | Chrysakis I.,Foundation for Research and Technology Hellas | And 2 more authors.
IISA 2014 - 5th International Conference on Information, Intelligence, Systems and Applications | Year: 2014

This paper presents the development of a new Web based LiDAR (Light Detection And Ranging) 3D point cloud viewer addressing mobility and portability issues arising from remote field applications by numerous multidisciplinary collaborative scientists. This new Web Browser-based 3D point cloud viewer, hereafter called 3DSYSTEK viewer, was developed and implemented in the framework of the3DSYSTEK research programme that aimed to develop tools to bring together all disciplines working to promote our cultural heritage through laser scanning, 3D modeling, 3D visualization, documentation, and exploitation of 3D data. 3D point cloud viewers' native implementations although they support multiple applications they are very expensive and their features vary from one software to another with considerable problems arising due to the introduction of personalized file formats by each individual native software. The presented 3DSYSTEK viewer is based on open-software, enables personalized expandability to address specific needs by individual users and allows the online remote collaboration amongst scientists at different locations as well as the widespread usage of the TLS surveying technology and 3D modeling of large monuments. © 2014 IEEE.


Kabassi K.,Technological Educational Institute of the Ionian Islands
Telematics and Informatics | Year: 2010

Internet has significantly influenced the tourism sector providing a great variety of services and products online. However, the number of choices has increased so dramatically that is very difficult for the consumers to find what they are looking for. For this purpose, recommendation systems for tourism have attracted a lot of research energy and interest. The main characteristic of these systems is that they can personalize their recommendations to each user interacting with the system. Personalization is even more essential for tourism recommendation systems used in handheld devices where the screen is even smaller and the presentation capabilities are limited. This paper addresses these problems and provides some development steps for a tourism recommendation system by making a state of the art in personalized e-tourism services both in computers and handheld devices as well as a review of the user modeling and personalization techniques used in these systems. Furthermore, the theories used for the improvement of the personalization procedure in tourism recommendation systems; their applications and evaluation are discussed. © 2009 Elsevier Ltd. All rights reserved.

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