67 research outputs found

    Goal-driven requirements analysis for hypermedia-intensive Web applications

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    Requirements analysis for Web applications still needs to employ effective RE practices to accommodate some distinctive aspects: capturing high-level communication goals, considering several user profiles, defining hypermedia-specific requirements, bridging the gap between requirements and Web design, and reusing requirements for an effective usability evaluation. Techniques should be usable, informal, require little training effort, and show relative advantage to project managers. On the basis of the i * framework, this paper presents a proposal for defining hypermedia requirements (concerning aspects such as content, interaction, navigation, and presentation) for Web applications. The model adopts a goal-driven approach coupled with scenario-based techniques, introduces a hypermedia requirement taxonomy to facilitate Web conceptual design, and paves the way for systematic usability evaluation. Particular attention is paid to the empirical validation of the model based on the perceived quality attributes theory. A case study developed with industrial partners is discusse

    Mastering the requirements analysis for communication-intensive websites

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    Web application development still needs to employ effective methods to accommodate some distinctive aspects of the requirements analysis process: capturing high-level communication goals, considering several user profiles and stakeholders, defining hypermedia-specific requirements (concerning navigation, content, information structure and presentation aspects), and reusing requirements for an effective usability evaluation. Techniques should be usable by both stakeholders and the design team, require little training effort, and show relative advantage to project managers. Over the last few years, requirements methodologies applied to web-based applications have considered mainly the transactional and operational aspects typical of traditional information systems. The communicational aspects of web sites have been neglected in regards to systematic requirements methods. This thesis, starting from key achievements in Requirements Engineering (hereafter RE), introduces a model (AWARE) for defining and analyzing requirements for web applications mainly conceived as strategic communication means for an institution or organization. The model extends traditional goal and scenario-based approaches for refining highlevel goals into website requirements, by introducing the analysis of ill-defined user goals, stakeholder communication goals, and a hypermedia requirement taxonomy to facilitate web conceptual design, and paving the way for a systematic usability evaluation. AWARE comprises a conceptual toolkit and a notation for effective requirements documentation. AWARE concepts and notation represent a useful communication and analysis conceptual tool that may support in the elicitation, negotiation, analysis and validation of requirements from the relevant stakeholders (users included). The empirical validation of the model is carried out in two ways. Firstly, the model has been employed in web projects on the field. These case studies and the lessons learnt will be presented and discussed to assess advantages and limits of the proposal. Secondly, a sample of web analysts and designers has been asked to study and apply the model: the feedback gathered is positive and encouraging for further improvement.Lo sviluppo di applicazioni web necessita di strumenti efficaci per gestire alcuni aspetti essenziali del processo di analisi dei requisiti: l'identificazione di obiettivi di comunicazione strategici, la presenza di una varietà di profili utente e di stakeholders, le definizione di requisiti ipermediali (riguardanti navigazione, interazione, contenuto e presentazione), e il riuso dei requisiti per una pianificazione efficace della valutazione dell'usabilità. Sono necessarie tecniche usabili sia dagli stakeholders che dai progettisti, che richiedono un tempo breve per essere appresi ed usati con efficacia, mostrando vantaggi significativi ai gestori di progetti complessi. La tesi definisce AWARE (Analysis of Web Application Requirements) - una metodologia per l'analisi dei requisiti specifica per la gestione di siti web (ed applicazioni interattive) con forti componenti comunicative. La metodologia estende le tecniche esistenti dell''analisi dei requisiti basate su approcci goal-oriented e scenario-based, introducendo una tassonomia di requisiti specifica per siti web (che permette di dare un input strutturato all'attività di progetazione), strumenti per l'identificazione e l'analisi di obiettivi ill-defined (generici o mal-definiti) e di obiettivi comunicativi e supporto metodologico per la valutazione dell'usabilità basata sui requisiti dell'applicazione. La metodologia AWARE è stata valutata sul campo attraverso progetti con professionisti del settore (web designers e IT managers), e grazie ad interventi di formazione in aziende specializzate nella comunicazione su web

    Euclidean matchings and minimality of hyperplane arrangements

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    We construct a new class of maximal acyclic matchings on the Salvetti complex of a locally finite hyperplane arrangement. Using discrete Morse theory, we then obtain an explicit proof of the minimality of the complement. Our construction provides interesting insights also in the well-studied case of finite arrangements, and gives a nice geometric description of the Betti numbers of the complement. In particular, we solve a conjecture of Drton and Klivans on the characteristic polynomial of finite reflection arrangements. The minimal complex is compatible with restrictions, and this allows us to prove the isomorphism of Brieskorn’s Lemma by a simple bijection of the critical cells. Finally, in the case of line arrangements, we describe the algebraic Morse complex which computes the homology with coefficients in an abelian local system

    The construction principle and non homogeneity of uncountable relatively free groups

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    In [11] Sklinos proved that any uncountable free group is not ℵ1\aleph_1-homogenenous. This was later generalized by Belegradek in [1] to torsion-free residually finite relatively free groups, leaving open whether the assumption of residual finiteness was necessary. In this paper we use methods arising from the classical analysis of relatively free groups in infinitary logic to answer Belegradek's question in the negative. Our methods are general and they also applications in varieties with torsion, for example we show that if VV contains a non-solvable group, then any uncountable VV-free group is not ℵ1\aleph_1-homogenenous

    Feeling Good in the Place We Live: The Moderating Role of the Perception of Environmental Resources in the Relationship between Values and Personal and Family Well-Being

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    The environmental psychological literature suggested that three different value orientations (egoistic, altruistic, and biospheric) are relevant for understanding environmental beliefs and intentions. We surveyed 365 Italian adults of different ages (range 18–87) to examine whether the egoistic, altruistic, and biospheric value orientations can lead to personal and/or family-related well-being. Additionally, it is examined whether the perception of presence and accessibility of two types of environmental resources (natural and urbanistic) related to ecosystem services can moderate the relation between value orientations and personal and family well-being. Results of moderation analyses showed that people with high biospheric values felt themselves as more satisfied if they perceived high and medium (but not low) presence or accessibility of natural resources in their environment, while people with high egoistic values perceived their family more satisfied if they perceived the high and medium (but not low) presence of good infrastructures in their environment of living. No significant moderation model emerged considering the participants’ altruistic values. The implications for environmental beliefs and well-being are discussed

    Fine-needle aspiration accuracy in the diagnosis of primary epithelioid angiosarcoma of the adrenal gland: a case report and review of the literature

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    Primary epithelioid angiosarcoma of the adrenal gland is extremely rare. Only 37 cases have been reported in the scientific literature.Here we describe the case of a 55-year-old woman affected by metastatic angiosarcoma in the right adrenal gland, who died few days after the histological diagnosis made by fine-needle aspiration (FNA). This is the second case of primary epithelioid angiosarcoma diagnosed by FNA among scientific articles published in English in PubMed. Microscopically, the tumor showed a predominant epithelioid differentiation, thus making the diagnostic process more difficult than usual. Immunohistochemical examination revealed positive reactivity for cytokeratin, CD31, and CD34. The literature shows that epithelioid adrenal angiosarcoma has poor clinical outcome, especially when metastatic at presentation

    The Role of Carbon Dioxide Laser Therapy in Penile Kaposi’s Sarcoma: A Case Series of Three HIV-Negative HHV-8-Positive Patients

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    Kaposi’s sarcoma (KS) is a rare tumor of vascular origin. It is quite common in HIV patients. It is rarely located on the glans penis, especially in HIV-negative patients (just some tens in the literature). Owing to the rarity of the disease, both the real impact on survival and the most suitable therapy are not known. However, in this 3-patient case series, carbon dioxide laser therapy was effective both for local control and survival. In fact, two late relapses but no disease-related death were recorded. Probably, KS in HIV-negative patients is a slowly progressive disease, not so aggressive as in HIV-positive patients. Laser therapy is easy, fast, and cheap, and may treat the disease radically. If these data are confirmed by further studies, in the foreseeable future, laser therapy may become the gold standard for treating HIV-negative patients affected by penile KS

    The baseline comorbidity burden affects survival in elderly patients with acute myeloid leukemia receiving hypomethylating agents: Results from a multicentric clinical study

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    Background: In older patients with acute myeloid leukemia (AML), the definition of fitness, prognosis, and risk of death represents an open question. Methods: In the present study, we tested the impact on survival of disease- and patient-related parameters in a large cohort of elderly AML patients homogeneously assigned to treatment with hypomethylating agents (HMAs). Results: In 131 patients with a median age of 76 years, we confirmed that early response (<0.001) and biology-based risk classification (p = 0.003) can select patients with better-predicted survival. However, a full disease-oriented model had limitations in stratifying our patients, prompting us to investigate the impact of baseline comorbidities on overall survival basing on a comorbidity score. The albumin level (p = 0.001) and the presence of lung disease (p = 0.013) had a single-variable impact on prognosis. The baseline comorbidity burden was a powerful predictor of patients' frailty, correlating with increased incidence of adverse events, especially infections, and predicted overall survival (p < 0.001). Conclusion: The comorbidity burden may contribute to impact prognosis in addition to disease biology. While the therapeutic armamentarium of elderly AML is improving, a comprehensive approach that combines AML biology with tailored interventions to patients' frailty is likely to fully exploit the anti-leukemia potential of novel drugs

    Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials

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    Quantum ESPRESSO is an integrated suite of computer codes for electronic-structure calculations and materials modeling, based on density-functional theory, plane waves, and pseudopotentials (norm-conserving, ultrasoft, and projector-augmented wave). Quantum ESPRESSO stands for "opEn Source Package for Research in Electronic Structure, Simulation, and Optimization". It is freely available to researchers around the world under the terms of the GNU General Public License. Quantum ESPRESSO builds upon newly-restructured electronic-structure codes that have been developed and tested by some of the original authors of novel electronic-structure algorithms and applied in the last twenty years by some of the leading materials modeling groups worldwide. Innovation and efficiency are still its main focus, with special attention paid to massively-parallel architectures, and a great effort being devoted to user friendliness. Quantum ESPRESSO is evolving towards a distribution of independent and inter-operable codes in the spirit of an open-source project, where researchers active in the field of electronic-structure calculations are encouraged to participate in the project by contributing their own codes or by implementing their own ideas into existing codes.Comment: 36 pages, 5 figures, resubmitted to J.Phys.: Condens. Matte
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