149 research outputs found

    Nanocrystalline Hydroxyapatite-Bisphosphonate Composites

    Get PDF
    The direct synthesis of hydroxyapatite─1,8-octan-bisphosphonic acid (HAp─BISPH) nanocrystals has been carried out in presence of increasing amounts of BISPH in solution, by hydrothermal method at 120 °C for 15 h. XRD, IR, NMR-MAS (31P, 1H and 13C), TEM, AFM, TGA and chemical analysis were used to characterize the structure, morphology and composition of the products. X-ray powder diffraction patterns show that the incorporation of bisphosphonate moieties induces a significant loss of the material crystallin-ity and a clear decrease of the crystallite size. TEM and AFM images show that the precipitated apatite particles prepared in the presence of this bisphosphonic acid are nanosized. The IR and NMR-MAS 1H spectroscopy show that the BISPH can replace the OH− groups of the apatitic structure. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3519

    Messaging Forensics In Perspective

    Get PDF
    This chapter presents the central theme and a big picture of the methods and technologies covered in this book (see Fig. 2.2). For the readers to comprehend presented security and forensics issues, and associated solutions, the content is organized as components of a forensics analysis framework. The framework is employed to analyze online messages by integrating machine learning algorithms, natural language processing techniques, and social networking analysis techniques in order to help cybercrime investigation

    Cybersecurity And Cybercrime Investigation

    Get PDF
    Society\u27s increasing reliance on technology, fueled by a growing desire for increased connectivity (given the increased productivity, efficiency, and availability to name a few motivations) has helped give rise to the compounded growth of electronic data. The increasing adoption of various technologies has driven the need to protect said technologies as well as the massive amount of electronic data produced by them. Almost every type of new technology created today, from homes and cars to fridges, toys, and stoves, is designed as a smart device, generating data as an auxiliary function. These devices are all now part of the Internet of Things (IoT), which is comprised of devices that have embedded sensors, networking capabilities, and features that can generate significant amounts of data. Not only has society seen a dramatic rise in the use of IoT devices, but there has also been a marked evolution in the way that businesses use these technologies to deliver goods and services. These include banking, shopping, and procedure-driven processes. These enhanced approaches to delivering added value create avenues for misuse and increase the potential for criminal activities by utilizing the digital information generated for malicious purposes. This threat requires protecting this information from unauthorized access, as this data (ranging from sensitive personal data, demographic data, business data, to system data and context data) can be monetized by criminals

    Impact of the buoyancy–viscous force balance on two-phase flow in layered porous media.

    Get PDF
    Motivated by geological carbon storage and hydrocarbon recovery, the effect of buoyancy and viscous forces on the displacement of one fluid by a second immiscible fluid, along parallel and dipping layers of contrasting permeability, is characterized using five independent dimensionless numbers and a dimensionless storage or recovery efficiency. Application of simple dimensionless models shows that increased longitudinal buoyancy effects increase storage efficiency by reducing the distance between the leading edges of the injected phase in each layer and decreasing the residual displaced phase saturation behind the leading edge of the displacing phase. Increased transverse buoyancy crossflow increases storage efficiency if it competes with permeability layering effects, but reduces storage efficiency otherwise. When both longitudinal and transverse buoyancy effects are varied simultaneously, a purely geometrical dip angle group defines whether changes in storage efficiency are dominated by changes in the longitudinal or transverse buoyancy effects. In the limit of buoyancy-segregated flow, we report an equivalent, unidimensional flow model which allows rapid prediction of storage efficiency. The model presented accounts for both dip and layering, thereby generalizing earlier work which accounted for each of these but not both together. We suggest that the predicted storage efficiency can be used to compare and rank geostatistical realizations, and complements earlier heterogeneity measures which are applicable in the viscous limit

    Formal Verification and Validation of UML 2.0 Sequence Diagrams using Source and Destination of Messages

    Get PDF
    AbstractA major challenge in software development process is to advance error detection to early phases of the software life cycle. For this purpose, the Verification and Validation (V&V) of UML diagrams play a very important role in detecting flaws at the design phase. It has a distinct importance for software security, where it is crucial to detect security flaws before they can be exploited. This paper presents a formal V&V technique for one of the most popular UML diagrams: sequence diagrams. The proposed approach creates a PROMELA-based model from UML interactions expressed in sequence diagrams, and uses SPIN model checker to simulate the execution and to verify properties written in Linear Temporal Logic (LTL). The whole technique is implemented as an Eclipse plugin, which hides the model-checking formalism from the user. The main contribution of this work is to provide an efficient mechanism to be able to track the execution state of an interaction, which allows designers to write relevant properties involving send/receive events and source/destination of messages using LTL. Another important contribution is the definition of the PROMELA structure that provides a precise semantics of most of the newly UML 2.0 introduced combined fragments, allowing the execution of complex interactions. Finally, we illustrate the benefits of our approach through a security-related case study in a real world scenario

    Applications of microsatellite markers for the characterization of olive genetic resources of tunisia

    Get PDF
    Among the countries of the Mediterranean Basin, Tunisia is located at the crossroad for the immigration of several civilizations over the last two millennia, becoming a strategic place for gene flow, and a secondary center of diversity for olive species. Olive is one of the principal crop species in Tunisia and now it strongly characterizes the rural landscape of the country. In recent years, collecting missions on farm and in situ were carried out by various institutes, with special emphasis given to ex situ collections serving as a reference for the identification of olive germplasm. Simple Sequence Repeats (SSRs) represent the easiest and cheapest markers for olive genetic fingerprinting and have been the tool of choice for studying the genetic diversity of this crop in Tunisia, to resolve cases of homonymy and synonymy among the commercialized varieties, to identify rare cultivars, to improve knowledge about the genetic variability of this crop, to identify a hot spot of olive biodiversity in the Tunisian oasis of Degache, and to enrich the national reference collection of olive varieties. The present review describes the state of the art of the genetic characterization of the Tunisian olive germplasm and illustrate the progress obtained through the SSR markers, in individuating interesting genotypes that could be used for facing incoming problems determined by climate changes

    Surdité professionnelle dans une industrie automobile de la région du centre Tunisien reconnaissance et indemnisation

    Get PDF
    Objectif : La surdité professionnelle pose encore des problèmes de reconnaissance et d’indemnisation en Tunisie. L’objectif de notre étude est d’analyser les conditions de reconnaissance et d’indemnisation de la surdité professionnelle auprès des travailleurs d’une industrie automobile.Matériel et méthodes : Nous avons mené une étude descriptive rétrospective qui a porté sur les salariés de la Société Tunisienne d’Industrie Automobile (STIA) victimes de surdité professionnelle reconnue par la Commission Médicale du centre sur une période de cinq ans (2003 à 2007).Résultats : Un total de 81 dossiers de surdité professionnelle reconnue a été colligé durant la période d’étude. Notre population était constituée par une main d’oeuvre masculine qualifiée (50,6%) et non qualifiée (38,3%) ayant une ancienneté moyenne dans le poste bruyant de 28,7 ± 6,8 ans. Le niveau moyen d’exposition professionnelle au bruit était de 90,7 ± 3,9dB(A). Il était plus élevé dans les ateliers de presse [92,4dB(A)], de tôlerie [91,6 dB(A)] et de peinture [90 dB(A)]. La perte auditive moyenne (PAM) sur la meilleure oreille était de 65,7 ± 17,4dB. Les potentiels évoqués auditifs ont été pratiqués chez 66 patients (81,5%) et ont confirmé le diagnostic de surdité de perception dans 64 cas et d’une surdité mixte dans les 2 autres cas. L’audiométrie tonale avec prothèse auditive a été pratiquée dans 71,6% des cas et a relevé une amélioration estimée nette chez 81% des patients. Le taux moyen de l’incapacitépermanente partielle était de 21,5 ± 6,8% avec des extrêmes allant de 8 et 51%. La majorité des salariés (92,6%) avaient un taux d’IPP entre 15 et 35%. La PAM > 60 dB a été statistiquement corrélée avec la catégorie professionnelle (p=0,017) et l’ancienneté au travail (p=0,039).Conclusion : La réparation de la surdité professionnelle présente encore des limites et des imperfections liées aux critères de reconnaissances qui doivent être révisées.Mots-clés : Surdité professionnelle, Bruit, Industrie automobile, Réparation

    Recovery, assessment, and molecular characterization of minor olive genotypes in Tunisia

    Get PDF
    Olive is one of the oldest cultivated species in the Mediterranean Basin, including Tunisia, where it has a wide diversity, with more than 200 cultivars, of both wild and feral forms. Many minor cultivars are still present in marginal areas of Tunisia, where they are maintained by farmers in small local groves, but they are poorly characterized and evaluated. In order to recover this neglected germplasm, surveys were conducted in different areas, and 31 genotypes were collected, molecularly characterized with 12 nuclear microsatellite (simple sequence repeat (SSR)) markers, and compared with 26 reference cultivars present in the Tunisian National Olive collection. The analysis revealed an overall high genetic diversity of this olive’s germplasm, but also discovered the presence of synonymies and homonymies among the commercialized varieties. The structure analysis showed the presence of different gene pools in the analyzed germplasm. In particular, the marginal germplasm from Ras Jbal and Azmour is characterized by gene pools not present in commercial (Nurseries) varieties, pointing out the very narrow genetic base of the commercialized olive material in Tunisia, and the need to broaden it to avoid the risk of genetic erosion of this species in this country

    Loss of Proliferation and Antigen Presentation Activity following Internalization of Polydispersed Carbon Nanotubes by Primary Lung Epithelial Cells

    Get PDF
    Interactions between poly-dispersed acid functionalized single walled carbon nanotubes (AF-SWCNTs) and primary lung epithelial (PLE) cells were studied. Peritoneal macrophages (PMs, known phagocytic cells) were used as positive controls in this study. Recovery of live cells from cultures of PLE cells and PMs was significantly reduced in the presence of AF-SWCNTs, in a time and dose dependent manner. Both PLE cells as well as PMs could take up fluorescence tagged AF-SWCNTs in a time dependent manner and this uptake was significantly blocked by cytochalasin D, an agent that blocks the activity of acto-myosin fibers and therefore the phagocytic activity of cells. Confocal microscopic studies confirmed that AF-SWCNTs were internalized by both PLE cells and PMs. Intra-trachially instilled AF-SWCNTs could also be taken up by lung epithelial cells as well as alveolar macrophages. Freshly isolated PLE cells had significant cell division activity and cell cycling studies indicated that treatment with AF-SWCNTs resulted in a marked reduction in S-phase of the cell cycle. In a previously standardized system to study BCG antigen presentation by PLE cells and PMs to sensitized T helper cells, AF-SWCNTs could significantly lower the antigen presentation ability of both cell types. These results show that mouse primary lung epithelial cells can efficiently internalize AF-SWCNTs and the uptake of nanotubes interfered with biological functions of PLE cells including their ability to present BCG antigens to sensitized T helper cells

    The Role of Alveolar Epithelial Cells in Initiating and Shaping Pulmonary Immune Responses: Communication between Innate and Adaptive Immune Systems

    Get PDF
    Macrophages and dendritic cells have been recognized as key players in the defense against mycobacterial infection. However, more recently, other cells in the lungs such as alveolar epithelial cells (AEC) have been found to play important roles in the defense and pathogenesis of infection. In the present study we first compared AEC with pulmonary macrophages (PuM) isolated from mice in their ability to internalize and control Bacillus Calmette-Guérin (BCG) growth and their capacity as APCs. AEC were able to internalize and control bacterial growth as well as present antigen to primed T cells. Secondly, we compared both cell types in their capacity to secrete cytokines and chemokines upon stimulation with various molecules including mycobacterial products. Activated PuM and AEC displayed different patterns of secretion. Finally, we analyzed the profile of response of AEC to diverse stimuli. AEC responded to both microbial and internal stimuli exemplified by TLR ligands and IFNs, respectively. The response included synthesis by AEC of several factors, known to have various effects in other cells. Interestingly, TNF could stimulate the production of CCL2/MCP-1. Since MCP-1 plays a role in the recruitment of monocytes and macrophages to sites of infection and macrophages are the main producers of TNF, we speculate that both cell types can stimulate each other. Also, another cell-cell interaction was suggested when IFNs (produced mainly by lymphocytes) were able to induce expression of chemokines (IP-10 and RANTES) by AEC involved in the recruitment of circulating lymphocytes to areas of injury, inflammation, or viral infection. In the current paper we confirm previous data on the capacity of AEC regarding internalization of mycobacteria and their role as APC, and extend the knowledge of AEC as a multifunctional cell type by assessing the secretion of a broad array of factors in response to several different types of stimuli
    corecore