94 research outputs found
Incidental discovery of testicular microlithiasis: What is the importance of ultrasound surveillance? Two case reports
No full textMany studies have demonstrated an association between diffuse bilateral testicular microlithiasis (TM) and gonadal and extragonadal germ cell tumors. Nevertheless, it is still uncertain whether ultrasound surveillance is really necessary in patients with TM in the absence of other risk factors such as previous testicular cancer, a history of cryptorchidism or testicular atrophy. We report the cases of a 33- and a 39-year-old man presenting with a retroperitoneal extragonadal tumor. The first patient underwent an MRI examination in order to rule out a lumbosacral hernia: MRI images showed no slipped disks but a voluminous retroperitoneal solid mass. The histological analysis revealed an immature teratoma. The second patient came to the emergency department complaining of abdominal pain, vomiting, weight loss and mild jaundice: ultrasound examination showed a large, ill-defined heterogeneous abdominal mass, confirmed by CT and MRI examination. The histology diagnosed a yolk sac tumor. In both patients, the testicular sonography was performed to rule out a focal lesion, but it displayed bilateral TM without a focal testicular mass. Based on our direct experience, we highlight the importance of annual ultrasonographic surveillance of the testis and the retroperitoneal space in patients with occasionally detected TM
The role of 3 Tesla diffusion-weighted imaging in the differential diagnosis of benign versus malignant cervical lymph nodes in patients with head and neck squamous cell carcinoma.
No full texthe aim of this study was to validate the role of diffusion-weighted imaging (DWI) at 3 Tesla in the differential diagnosis between benign and malignant laterocervical lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods. Before undergoing surgery, 80 patients, with biopsy proven HNSCC, underwent a magnetic resonance exam. Sensitivity (Se) and specificity (Spe) of conventional criteria and DWI in detecting laterocervical lymph node metastases were calculated. Histological results from neck dissection were used as standard of reference. Results. In the 239 histologically proven metastatic lymphadenopathies, the mean apparent diffusion coefficient (ADC) value was 0.903 x 10-3 mm2/sec. In the 412 pathologically confirmed benign lymph nodes, an average ADC value of 1.650 x 10"3 mm2/sec was found. For differentiating between benign versus metastatic lymph nodes, DWI showed Se of 97% and Spe of 93%, whereas morphological criteria displayed Se of 61% and Spe of 98%. DWI showed an area under the ROC curve (AUC) of 0.964, while morphological criteria displayed an AUC of 0.715. Conclusions. In a DWI negative neck for malignant lymph nodes, the planned dissection could be converted to a wait-and-scan policy, whereas DWI positive neck would support the decision to perform a neck dissection
A Framework to Support Interoperability and Multi-channel Delivery Among Heterogeneous Systems: TRAME Project
No full textThe e-commerce has become a point of strength for the companies that desire to increase their billing enlarging their clients park and reducing the management costs. Therefore the demand has been born to use platforms able to support the interoperability between heterogeneous systems and the multi-channelling with variegated devices to access different services in reliable manner and to allow, so, a spread of the market toward partner with particular needs. Furthermore, many available services have been typically designed for a single channel the web one. In a real world scenario, an ever-growing number of users take advantage of different kind of communication channel and devices. In this paper we propose a B2B oriented framework able to support the interoperability among heterogeneous systems developed according to the ebXML reference model for the business messages interchange suitable to any B2B marketplace that foresees the commercial interaction among partners with different roles and profiles (including channel and device). Such framework has been developed and experimented for the TRAME research project that has as objective to create a room of district compensation of the peaks of productive ability demands within the Textile/Clothing sector and to give the needed infrastructure for the business messages exchange among the partners of the productive spinneret
Loading and Rendering Optimization for Networked Virtual Worlds
No full textInternet-based collaborative virtual environments allow users to explore and interact with many virtual worlds containing a very large number of objects that are downloaded in real time rather than been pre-distributed. Client’s bandwidth fluctuation during the enjoyment of particularly complex environments, can produce a bottleneck that generates very long downloading and rendering time. This bottleneck can compromise the correct enjoyment of collaborative virtual environments, arising synchronization and shard state consistency problems that are keys factors in these applications. To avoid too much long waiting times during objects’ download, we have developed a method to reduce bandwidth congestion. This is possible thanks to the download of only the exact portion of geometries that is necessary for rendering, according to its own field of view and to the semantic rules defined by the designer during the phase of contents population. Such approach consists in the use of a data structure that is based on different levels of priority and allows in this way a selective download. We have applied this solution to WT04 framework which is a research project whose aim is to achieve a framework for generating and enjoining 3D collaborative virtual experiences. WT04 framework supports collaborative rules definitions suitable to perfectly govern virtual experiences
A Framework to Generate 3D Learning Experiences
No full textA Collaborative Virtual Environment (CVE) is a computer-based virtual space that supports collaborative work and social interplay. In a 3D CVE, a ‘hosting’ 3D world is the necessary
ingredient: within it users provided with graphical embodiments called avatars that convey their identity (presence, location, movement etc.), can meet and interact with other users,
with agents or with virtual objects. Even if graphics hardware and 3D technologies are rapidly evolving and the increased Internet connection speed allows the sharing of amounts of data and information among geographically distributed users, the development of networked three-dimensional applications is still complicated and requires expert knowledge. Although some collaborative 3D Web technologies and applications have already been developed, most of them are particularly concerned with offering a high level realistic representation of the
virtual world since increasing the level of detail increases the sense of ‘virtual presence’ in the 3D world. However, these developments have not, at the same time supported a high
level, non-expert authoring process and the concepts of programming flexibility and component re-use have rarely been taken into account.
In this introduction, we discuss our research experience in the field of Collaborative Virtual Environments. We will outline our approach which has been based on both multi-channel
integration and on high performances issues
3DC PLUS: An Authoring Toolkit for Collaborative Virtual Environments
No full textIn recent years, the hardware technology, high bandwidth network and 3D graphics systems have brought the Virtual Reality (VR) technology into a new field: Collaborative Virtual Environments (CVE) This field’s goal consists of using computers as tools for communication and information share through the use of 3D shared spaces to provide collaboration facilities . Even if, in the same time, also 3D design and virtual environments au-thoring tools has been developed, their main goal is mainly directed to support professional designers in the modeling of 3D words through advanced techniques for shapes and surfaces manipulation allowing multiple ef-fects to improve the rendering of the scene without offer any specific support to more closely related interaction control issues. When creating a virtual reality environments, in fact, a large amount of interactions have to be programmed. The main problem as for this is that non-computer expert users lack the programming skills neces-sary to create useful applications. Specifying interactions and behaviors remains in the domain of the program-mers. This paper examines the problem of creating authoring tools for VE that allow non-expert users to produce effective CVE applications without the direct programmers assistance. Then we propose a toolkit to support the entire process of designing, composing and deploying a Collaborative Virtual Environment in a visual mode based on the WYSIWYG paradigm that WT04 engine can process and evolve. WT04 is a research project to achieve a framework for generating and enjoining 3D collaborative virtual experiences. WT04 framework sup-ports collaborative rules definitions suitable to fully govern virtual experiences: virtual meeting during which users join to virtual session in the same time and in the same virtual environments with the help of a guide ex-plaining the contents and aiding the collaboration between users to achieve same particular goals according to well defined collaboration rules. Hence, main dynamic aspects that govern experiences are environment and ob-jects configuration, content definition and collaboration rules specification applying to each particular session
WebTalk04: a Declarative Approach to Generate 3D Collaborative Environments
No full textEven if graphics hardware and 3D technologies are rapidly evolving and the increased internet connection speed allows to share amount of data and information between user geographically distributed, the development of networked three-dimensional applications is still complicated and demands expert knowledge. Though some collaborative Web 3D technologies and applications had already been developed, most of them are concerned especially to offer an high level realistic representation of the virtual world as increasing the level of detail would mean to increase the “virtual presence” sense in the 3D world; at the same time they don’t support from one hand an high level, non-expert authoring process, from the other the concept of programming flexibility and of component reuse is rarely taken into account.
We advocate the need of drastically simplify authoring and personalization phases through formal description of the interaction’s sets as well as of the behavioural features and rules, that we call “collaborative metaphors”, in a component oriented fashion to drive collaboration among users in the specific way a designer is intended to do. As result of previous considerations we present WebTalk04, a declarative 3D component system based on XML documents describing not only the environment formal structure of the virtual world were the action take place but also the complex interaction set of rules that control interactions between users and world objects used to stimulate certain kind of collaboration, thus effectively help fast prototyping and an easy building up of such collaborative applications. The WebTalk04 system also provide a runtime 3D rendering engine fully configurable through XML in order to easily modify virtual world settings as well as collaborative interaction rules thus allowing to control independently geometries, behaviors and contents, assigning to different developer (i.e software developer , content developer , graphics developer , session designers) different task
Mobile WebTalk: a framework to support ubiquitous collaboration
No full textMobile technologies offer the opportunity to embed learning in a natural environment. This paper describes the design of the UbiCrossWords prototype, a project built to explore the opportunities to support learning through an orientation game in a mixed reality environment. The paper first introduces the scenario and then describes the general architecture of the prototype. Then the paper explores how using mobile technologies in direct physical interaction with space and with other players can be combined with principles of engagement and self-motivation to create a powerful learning experience. Finally it presents the underlying architecture, Mobile WebTalk, a mixed CVE framework mainly used for collaborative educational aims, to support in a flexible way both stationary and mobile players. We explore the use of heterogeneous collaboration thought a software architecture, running on mobile devices, able to configure itself on the basis of a XML declaration representing workspace and interaction rules shared with the 3D stationary users
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