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The practice of defect analysis is recognized as an essential task for software process measurement, yet its effective application in the industrial development of large-scale software systems raises several challenges. We report the results of a study conducted at SELEX ES - a large system integrator leader in the market of software-intensive mission-critical systems. The article describes the defect analysis approach that we tailored to evaluate the software development process with respect to the quality of produced software and its relation with the required effort. Three key phases of the process were addressed, regarding the software implementation, the testing phase and the prerelease defect fixing activity, over a set of six computer software configuration items developed from 2009 to 2012 for the naval and maritime domain product line. The analysis highlighted efficiency bottlenecks in each of the monitored phases, providing company engineers with insights about room for process improvement. The implemented approach, the observed phenomena and the inferred conclusions are of support to practitioners coping with systems, development models and industrial environments similar to the considered one.

Cloud Computing has been receiving great attention in the last few years due to the benefits it provides in terms of flexibility, scalability, virtualization and service provision. Nevertheless, many companies remain reluctant to such a cutting-edge technology due to the serious security issues affecting virtualized environments, especially in critical application scenarios where high safety and dependability levels are required. This work is aimed at discussing and presenting the main security threats for cloud computing infrastructures, as well as proposing a novel architecture in charge of reacting to security attacks in Infrastructure as a Service platforms. The basic idea is to migrate the attacked virtual appliance and to reconfigure the network by means of Software Defined Networking approach. The paper presents the architecture we have in mind and that will be deployed and validated against a real world distributed Air Traffic Control system, for which missing dependability and security targets would result in huge business and human losses.

The increasing usage of wireless sensor networks in large scale and safety critical monitoring applications scenarios exacerbates their well known energy and scalability limitations. Organizing the network in clusters is what the most of the existing solutions propose to dominate network complexity, as well as to define quality of service policies in charge of fitting application requirements. However, this demands for an extra effort in terms of network setup and circulating messages among nodes which have a non negligible impact on energy consumption at network level. This work improves the state of the art in the field of communication protocols for clustered networks by proposing a new topology control and recovery mechanism which exhibits low energy demands. This aims to let randomly deployed sensors to self organize in a well constructed topology, as well as to repair the network from potential crashes. The existence of a path from any sensor to the sink, composed only by cluster heads, is guaranteed thus further reducing the energy consumption. The simulation tests show encouraging results even in the case of very large and dense networks.

The Air Traffic Management (ATM) domain is moving from fragmented systems towards a single sky. SWIM is the world recognized technological programme aiming to support in- formation sharing and data exchange in the next generation ATM systems. A prototype of the SWIM architecture has been realized in the framework of the SWIM-SUIT project, which is the focus of this paper. It reports practical ex- perience gained by SELEX-SI 1, developers when coping with data distribution task over these systems, both from a methodological and technological perspective.

Mobile Peer-to-Peer (P2P) is a base paradigm for many new killer applications for mobile ad-hoc networks and the Mobile Internet. Currently, it is not well understood whether this paradigm is able to meet business and consumer dependability expectations. Dependability assessment of P2P applications can be achieved by field failure data analysis. The collection of failure data from wireless ad-hoc networks is a challenging task due to the intermittent usage and the mobility of users that do not allow to measure time-based dependability parameters. For this reason, we propose to deploy automated workloads on the actual peer nodes which have to operate continuously. Specifically, this paper formalizes the problem and presents the design of a workload for mobile P2P that aims to orchestrate the peers uniformly, letting the failure occurrence be independent of the network load. Simulation results and experimentation over an actual Bluetooth network demonstrate that the proposed workload meets the defined requirements.

Rare tumor of the oral cavity presenting as a gingival swelling without bone involvement was present. The lesion, resected for mastication troubles, histologically presented a basaloid cell proliferation predominantly organized in nests formed by a peripheral palisading of cells with apically disposed nuclei. Immunohistochemical stainings for the cytokeratin 19 and Ber-EP4 showed a marked and diffuse positivity for the former, while the latter was negative. These results support the diagnosis of peripheral ameloblastoma and allow us to distinguish it from the basal cell carcinoma, which shares some histological features with this unusual tumor of the oral cavity.

The carcinoma of the jejunum represents 3-6.5% of gastric intestinal tumors and 33-50% of small intestine carcinomas. The observation of a case of jejunum carcinoma has offered the authors the idea for a critical revision on the subject. After an examination on the diagnostic, anatomopathological, clinical and therapeutic problems, the authors underline the importance of the precocious diagnosis of neoplasia; in fact the jejunum carcinoma is characterized by a hidden and aspecific symptomatology and by dangerous evolution; besides the site is difficult for an organic study with the common methods of investigation. Therefore, in all patients in whom the suspicion of a jejunum pathology exists, it is indispensable to carry out a precise diagnostic iter which is based on radiological endoscopic and tomographic investigation: in fact the small intestine and the jejunum in particular are intestinal tracts that are explored with difficult and therefore at times only an accurate effecting of the radiological study can permit a precocious diagnosis the only valid supposition for the carrying out of a truly radical surgical therapy and for the acquiring of a batter prognosis.

Filaggrin is a protein normally present in the granular and horny layer of stratified squamous epithelia. We studied the presence of this protein in 83 benign lesions and in 73 cases of malignant epithelial tumours of the oral cavity and investigated its possible role as an immunohistochemical marker. The immunohistochemical technique was based on the P.A.P. method. The results in benign lesions show a distribution of filaggrin similar to that observed in the normal mucosa. By contrast, an irregular distribution of filaggrin is observed in areas of leukoplakia with parakeratosis and in papillomas. In malignant lesions the expression of this protein is closely related to the degree of differentiation of the cellular elements, being positive in more differentiated and negative in anaplastic areas. Therefore in some types of benign lesions filaggrin testifies an alteration of the normal process of keratinization. Filaggrin is more significant in malignant lesions in which its presence if any permits an evaluation of the degree of differentiation of the tumour.

Summary 183 cases of soft tissue tumors were studied utilizing the immunoperoxidase technique to demonstrate alpha-1-antitrypsin, ferritin and lysozyme. The series comprises SO malignant lesions, 34 intermediate malignancy lesions, 99 benign lesions of fibrohistiocytic origin, and 23 malignant tumors of non fibrohistiocytic origin. The actual results of the study are as follows: alpha-1-antitrypsin, ferritin and lysozyme were always absent in 10 fibrosarcomas, 2 liposarcomas, 2 Ewing sarcomas, 3 synovial sarcomas, 4 neuro fibrosarcomas, and 2 rhabdomyosarcomas, but in 24 malignant fibrous histiocytomas, 34 cases of dermato fibrosarcoma protuberans and 102 benign fibrohistiocytic lesions, these activities were present in a percentage that ranged between 12% and 38% (average 25%). Differences in the frequency of positive reactions did not occur between benign and malignant fibrobistiocytic lesions. The immunohistological examinations carried out have, therefore, only a very limited value for the practical diagnostic evaluation, but, when positive, are important to clarify the histogenesis of the tumor.

A case of malignant fibrous histiocytoma occurring in the gingival tissue on the site of the mandibular right canine is reported. The histological, histochemical, immunohistochemical and ultrastructural features are discussed and compared with the recent literature on malignant fibrous histiocytomas.

Summary Metastases from an atypical fibroxantboma of skin have been reported but are very few in the literature. We had a personal case which, originally localized on the nostril, gave metastases to the cervical regional lymph node with no local recurrence. We examined both the primary and metastatic tumor by conventional histological stains and by immunoperoxidase technique to localize lysozyme, alpha-1-antitrypsin, ferritin and factor VIII antigens. The results show a clear correspondence between the primary and metastatic tumor.

By hystological and electronmicroscopical study liver of rats treated with tiadenol at a daily dose of 100 and 200 mg for 30 days, we could demonstrate: lack of necrosis and interstitial phlogosis and, especially in those animals treated with greater doses, numerical increase of peroxisomes, hypertrophy of SER and RER and a lesser regularity of glycogen distribution.

We investigated involvement of the peripheral nervous system in 6 patients with amyotrophic chorea-acanthocytosis. Electromyographic and neurographic findings, and pathological changes as demonstrated by examination of biopsy specimens of muscle and sural nerve indicate that most patients had an axonal sensorimotor polyneuropathy with more pronounced involvement of the distal portion of the nerves. Results obtained in one patient raised the question of an anterior horn cell disorder.