Gender differences in digital music distribution methods

This study examines gender differences among Greek Internet users in using digital music distribution methods. First, a Web-based questionnaire was developed and placed on most popular Greek forums. Then, 300 Greek Internet users stated their opinions regarding digital music and the following downloading methods: 1) Http downloading, 2) P2P downloading, 3) Torrent downloading, and 4) Combined iTunes method. The results revealed that P2P programs are the first choice for downloading mp3. The responders were satisfied with the P2P’s easiness of use, the variety of songs and the no need to pay. However, they worried about P2P’s safety. Gender differences were identified in several areas. Music industry managers could consider these findings in their strategies to reach the consumers. Advertising companies could use the results to target differently male or female consumers.     

A policy-based B2C e-Contract management workflow methodology using semantic web agents

Since e-Commerce has become a discipline, e-Contracts are acknowledged as the tools that will assure the safety and robustness of the transactions. A typical e-Contract is a binding agreement between parties that creates relations and obligations. It consists of clauses that address specific tasks of the overall procedure which can be represented as workflows. Similarly to e-Contracts, Intelligent Agents manage a private policy, a set of rules representing requirements, obligations and restrictions, additionally to personal data that meet their user’s interests. In this context, this study aims at proposing a policy-based e-Contract workflow management methodology that can be used by semantic web agents, since agents benefit from Semantic Web technologies for data and policy exchanges, such as RDF and RuleML that maximize interoperability among parties. Furthermore, this study presents the integration of the above methodology into a multi-agent knowledge-based framework in order to deal with issues related to rules exchange where no common syntax is used, since this framework provides reasoning services that assist agents in interpreting the exchanged policies. Finally, a B2C e-Commerce scenario is presented that demonstrates the added value of the approach.     

Optimal Design of Blocked and Split-Plot Experiments for Fixed Effects and Variance Component Estimation

In general, modeling data from blocked and split-plot response surface experiments requires the use of generalized least squares and the estimation of two variance components. The literature on the optimal design of blocked and split-plot response surface experiments, however, focuses entirely on the precise estimation of the fixed factor effects and completely ignores the necessity to estimate the variance components as well. To overcome this problem, we propose a new Bayesian optimal design criterion which focuses on both the variance components and the fixed effects. A novel feature of the criterion is that it incorporates prior information about the variance components through log-normal or beta prior distributions. The resulting designs allow for a more powerful statistical inference than traditional optimal designs. In our algorithm for generating optimal blocked and split-plot designs, we implement efficient quadrature approaches for the numerical approximation of the new optimal design criterion. Supplementary materials for this article are available online.     

The Trees of the Sacred Natural Sites of Zagori,NW Greece

Cultural landscapes can often be identified by the presence of sacred trees which have been retained and can be recognised as distinctive veteran trees. The characteristics of these trees such as huge size and longevity give them an enduring presence in the landscape, while their conceptualisation as the ‘domesticated’ wild, transform them into symbols of spirituality and local history. In Zagori, NW Greece, trees gain sanctity by virtue of proximity or connection with sacred sites often associated with churches. In these sites, trees can grow into natural shapes as a result of strong taboos, which prevent use for private needs. There is an association between tree species and the nature of the sacred site: broadleaved oaks and maples are associated with outlying churches; plane trees are located in central squares, next to the church and provide a focal point for community life, while in cemeteries native evergreens are nowadays replaced by planted conifers. In the present day local communities appreciate sacred trees as living elements of their collective memory and local history.     

Detection, quantification and vitality of Listeria monocytogenes in food as determined by quantitative PCR

In this paper we describe the development of a quantitative PCR (qPCR) technique to detect, quantify and determine the vitality of Listeria monocytogenes in foods. The method was based on the amplification of the intergenic region spacer (IGS) between the 16S and 23S rRNA genes. A panel of more than 100 strains of Listeria spp. and non-Listeria was used in order to verify the specificity of the primers and Taqman probe and amplification signals were obtained only when L. monocytogenes DNA and RNA were loaded in the qPCR mix. Standard curves were constructed in several food matrices (milk, meat, soft cheese, fermented sausage, cured ham and ready-to-eat salad). The quantification limit was of 10(3)-10(4) cfu/g or ml, while for the determination of vitality it was 10(4)-10(5) cfu/g or ml. After an overnight enrichment in BHI at 37 degrees C also 10 cfu/g or ml could be detected in all the matrices used in this study. When we applied the protocol to food samples collected from the market or from small food processing plants, on a total number of 66 samples, 4 fresh cheeses from raw milk gave positive results prior to the overnight incubation, while 9 samples, of which only one represented by fresh meat and the others by cheeses from raw milk, were positive after the enrichment. Out of the 4 positive samples, only one could be quantified and it was determined to contain 4x10(3) cfu/g.     

Spoilage of blood sausages morcilla de Burgos treated with high hydrostatic pressure

In this study, the microbial ecology of the blood sausage morcilla de Burgos, subjected to high hydrostatic pressure treatment (HPP), was studied by culture-dependent and -independent methods. Morcilla de Burgos is the most traditional and famous blood sausage in Spain. The producers are interested in extending its shelf-life in order to expand their market and to reduce losses attributed to spoilage. Sausage batter prior to stuffing and blood sausages HPP treated or not (control) were analyzed at 0, 9, 14, 21, 28 and 35 days of storage at 4 degrees C. Lactic acid bacteria, Pseudomonas spp. and aerobic mesophilic bacteria were investigated by traditional plating. PCR-denaturing gradient gel electrophoresis (DGGE) was used to analyze the DNA and the RNA extracted directly from the blood sausages, as well as bulk cells of LAB and Pseudomonas spp. The results showed that HPP improved the shelf life of morcilla de Burgos to 28 days in comparison with control samples. The populations responsible for spoilage, namely LAB, remained lower in HPP treated samples when compared with the control samples. Only at 35 days of storage they reached values of 10(8) cfu/g, leading to the spoilage of the product. Although, HPP affected the LAB population, they were able to recover the injury provoked by the treatment. Lastly, HPP seemed to affect differently LAB species detected. While Leuconostoc mesenteroides was completely inactivated by HPP, Weissella viridescens was able to recover and carry out the typical spoilage of the product. Pseudomonas spp. remained under detection level (<10(2) CFU/g) after the HPP treatment.     

Fibro/chondrogenic differentiation of dental stem cells into chitosan/alginate scaffolds towards temporomandibular joint disc regeneration

Tissue engineering (TE) may provide effective alternative treatment for challenging temporomandibular joint (TMJ) pathologies associated with disc malpositioning or degeneration and leading to severe masticatory dysfunction. Aim of this study was to evaluate the potential of chitosan/alginate (Ch/Alg) scaffolds to promote fibro/chondrogenic differentiation of dental pulp stem cells (DPSCs) and production of fibrocartilage tissue, serving as a replacement of the natural TMJ disc. Ch/Alg scaffolds were fabricated by crosslinking with CaCl2 combined or not with glutaraldehyde, resulting in two scaffold types that were physicochemically characterized, seeded with DPSCs or human nucleus pulposus cells (hNPCs) used as control and evaluated for cell attachment, viability, and proliferation. The DPSCs/scaffold constructs were incubated for up to 8 weeks and assessed for extracellular matrix production by means of histology, immunofluorescence, and thermomechanical analysis. Both Ch/Alg scaffold types with a mass ratio of 1:1 presented a gel-like structure with interconnected pores. Scaffolds supported cell adhesion and long-term viability/proliferation of DPSCs and hNPCs. DPSCs cultured into Ch/Alg scaffolds demonstrated a significant increase of gene expression of fibrocartilaginous markers (COLI, COL X, SOX9, COM, ACAN) after up to 3 weeks in culture. Dynamic thermomechanical analysis revealed that scaffolds loaded with DPSCs significantly increased storage modulus and elastic response compared to cell-free scaffolds, obtaining values similar to those of native TMJ disc. Histological data and immunochemical staining for aggrecan after 4 to 8 weeks indicated that the scaffolds support abundant fibrocartilaginous tissue formation, thus providing a promising strategy for TMJ disc TE-based replacement.

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Identification of Rare LRP5 Variants in a Cohort of Males with Impaired Bone Mass

Osteoporosis is the most common bone disease characterized by reduced bone mass and increased bone fragility. Genetic contribution is one of the main causes of primary osteoporosis; therefore, both genders are affected by this skeletal disorder. Nonetheless, osteoporosis in men has received little attention, thus being underestimated and undertreated. The aim of this study was to identify novel genetic variants in a cohort of 128 males with idiopathic low bone mass using a next-generation sequencing (NGS) panel including genes whose mutations could result in reduced bone mineral density (BMD). Genetic analysis detected in eleven patients ten rare heterozygous variants within the LRP5 gene, which were categorized as VUS (variant of uncertain significance), likely pathogenic and benign variants according to American College of Medical Genetics and Genomics (ACMG) guidelines. Protein structural and Bayesian analysis performed on identified LRP5 variants pointed out p.R1036Q and p.R1135C as pathogenic, therefore suggesting the likely association of these two variants with the low bone mass phenotype. In conclusion, this study expands our understanding on the importance of a functional LRP5 protein in bone formation and highlights the necessity to sequence this gene in subjects with idiopathic low BMD.     

Corrosion and protection of carbon steel in low enthalpy geothermal fluids. The case of SOUSAKI IN Greece

This experimental work is aimed at evaluating first, the effect of a solution simulating the geothermal fluid of the field in Sousaki, New Korinthia, on the corrosion of bare steel, and, second, the protective performance that certain combinations of organic coatings provide. This evaluation resulted from corrosion potential measurements, mass loss measurements, corrosion rate estimates by the Tafel method, and visual ranking of the degree of rusting and blistering. Six combinations of organic coatings were tested. Four of them consisted of water-based paints as primer, as well as intermediate and topcoat. Of the two remaining combinations, the first comprised a water-based primer, including dispersed tannin and a two-component epoxy resin topcoat, while the second consisted of a two-component acrylic primer, containing chromate pigments and the same epoxy resin topcoat as above. All coating combinations tested exhibited protective performance. The results of the water-based coatings were less satisfactory than those of the two combinations containing the epoxy resin topcoat.