Search

We consider a road network represented by a directed graph. We assume to collect many measurements of traffic flows on all the network arcs, or on a subset of them. We assume that the users are divided into different groups. Each group follows a different path. The flows of all user groups are modeled as a set of independent Poisson processes. Our focus is estimating the paths followed by each user group, and the means of the associated Poisson processes. We present a possible solution based on a Dynamic Programming algorithm. The method relies on the knowledge of high order cumulants. We discuss the theoretical properties of the introduced method. Finally, we present some numerical tests on well-known benchmark networks, using synthetic data.

We address the problem of parameter identification for the standard pharmacokinetic/pharmacodynamic (PK/PD) model for anesthetic drugs. Our main contribution is the development of a global optimization method that guarantees finding the parameters that minimize the one-step ahead prediction error. The method is based on a branch-and-bound algorithm, that can be applied to solve a more general class of nonlinear regression problems. We present some simulation results, based on a dataset of twelve patients. In these simulations, we are always able to identify the exact parameters, despite the non-convexity of the overall identification problem.

BACKGROUNDː To achieve a consensus on the minimum set of outcome measures and predictors to be used in the neurosurgical practice and on the timing of outcome assessment. METHODSː A consensus building approach was employed. All neurosurgical departments in Lombardy (Italy) were invited to participate by the Fondazione IRCCS Istituto Neurologico Carlo Besta. Three workshops were organized during which a multidisciplinary group called Neurosurgical Outcome Network (NEON) was created and the methodology to select outcome measures, predictors, and timing of outcome assessment was established. Eight working groups were created for the different neurosurgical diseases (neuro-oncological, skull base, vascular, traumatic, spinal, peripheral nervous system, malformation, functional) and 8 workshops were organized to identify the outcome measures and predictors specific for each of the neurosurgical diseases based on the experts’ clinical practice and the existing literature. RESULTSː A total of 20 neurosurgical departments participated in this study. Specific outcome measures, predictors and the timing of outcome assessment were identified for each of the 8 neurosurgical diseases. Moreover, a list of variables common to all pathologies were identified by the NEON group as further data to be collected. CONCLUSIONSː A consensus on the minimum set of outcome measures and predictors and the timing of outcome assessments for 8 neurosurgical diseases was achieved by a group of neurosurgeons of the Lombardy region, called NEON. These sets could be used in future studies for a more homogeneous data collection and as a starting point to reach further agreement also at national and international level.

Background: The aim of this study was to achieve a consensus on the minimum set of outcome measures and predictors to be used in the neurosurgical practice and on the timing of outcome assessment. Methods: A consensus building approach was employed. All neurosurgical departments in Lombardy (Italy) were invited to participate by the Carlo Besta Neurologic Institute IRCCS Foundation. Three workshops were organized during which a multidisciplinary group called Neurosurgical Outcome Network (NEON) was created and the methodology to select outcome measures, predictors, and timing of outcome assessment was established. Eight working groups were created for the different neurosurgical diseases (neuro-oncological, skull base, vascular, traumatic, spinal, peripheral nervous system, malformation, functional) and 8 workshops were organized to identify the outcome measures and predictors specific for each of the neurosurgical diseases based on the experts' clinical practice and the existing literature. Results: A total of 20 neurosurgical departments participated in this study. Specific outcome measures, predictors and the timing of outcome assessment were identified for each of the 8 neurosurgical diseases. Moreover, a list of variables common to all pathologies were identified by the NEON group as further data to be collected. Conclusions: A consensus on the minimum set of outcome measures and predictors and the timing of outcome assessments for 8 neurosurgical diseases was achieved by a group of neurosurgeons of the Lombardy region, called NEON. These sets could be used in future studies for a more homogeneous data collection and as a starting point to reach further agreement also at national and international level.

(1) Background: Neuroimaging differentiation of glioblastoma, primary central nervous system lymphoma (PCNSL) and solitary brain metastasis (BM) represents a diagnostic and therapeutic challenge in neurosurgical practice, expanding the burden of care and exposing patients to additional risks related to further invasive procedures and treatment delays. In addition, atypical cases and overlapping features have not been entirely addressed by modern diagnostic research. The aim of this study was to validate a previously designed and internally validated ResNet101 deep learning model to differentiate glioblastomas, PCNSLs and BMs. (2) Methods: We enrolled 126 patients (glioblastoma: n = 64; PCNSL: n = 27; BM: n = 35) with preoperative T1Gd-MRI scans and histopathological confirmation. Each lesion was segmented, and all regions of interest were exported in a DICOM dataset. A pre-trained ResNet101 deep neural network model implemented in a previous work on 121 patients was externally validated on the current cohort to differentiate glioblastomas, PCNSLs and BMs on T1Gd-MRI scans. (3) Results: The model achieved optimal classification performance in distinguishing PCNSLs (AUC: 0.73; 95%CI: 0.62–0.85), glioblastomas (AUC: 0.78; 95%CI: 0.71–0.87) and moderate to low ability in differentiating BMs (AUC: 0.63; 95%CI: 0.52–0.76). The performance of expert neuro-radiologists on conventional plus advanced MR imaging, assessed by retrospectively reviewing the diagnostic reports of the selected cohort of patients, was found superior in accuracy for BMs (89.69%) and not inferior for PCNSL (82.90%) and glioblastomas (84.09%). (4) Conclusions: We investigated whether the previously published deep learning model was generalizable to an external population recruited at a different institution—this validation confirmed the consistency of the model and laid the groundwork for future clinical applications in brain tumour classification. This artificial intelligence-based model might represe

The pebble motion on trees (PMT) problem consists in finding a feasible sequence of moves that repositions a set of pebbles to assigned target vertices. This problem has been widely studied because, in many cases, the more general Multi-Agent path finding (MAPF) problem on graphs can be reduced to PMT. We propose a simple and easy to implement procedure, which finds solutions of length O(knc + n^2), where n is the number of nodes, $k$ is the number of pebbles, and c the maximum length of corridors in the tree. This complexity result is more detailed than the current best known result O(n^3), which is equal to our result in the worst case, but does not capture the dependency on c and k.

Introduction: Intradiploic pseudomeningoceles, also called intradiploic cerebrospinal fluid (CSF) fistulas, are abnormal CSF collection between the two bony tables of the calvaria resulting from post-surgical CSF leakage. To date, only six cases of intradiploic pseudomeningocele have been reported, all occurring in the occipital area. In this paper, we report the seventh case of late-onset occipital intradiploic pseudomeningocele (OIP) occurring in a young female patient who underwent surgery for the removal of a cerebellar pilocytic astrocytoma. At this regard, we also review the literature on the few recognized cases of OIP. Case presentation: The case of an 18-year-old female patient known to our institute for an operation 12 years earlier to remove a pilocytic astrocytoma is illustrated. At admission the patient complained only of occasional orthostatic headache. Brain imaging demonstrated a pseudomeningocele extended intradiploically from the occipital squama to the condylar and clivus regions, thinning both occipital bone tables and dilating the CSF-filled diploe. Watertight duroplasty and cranioplasty were effectively performed. Conclusion: Pediatric patients undergoing posterior cranial fossa craniotomy/craniectomy may postoperatively develop OIP. In this setting, treatment of any dural CSF fistula should be considered because of the risk of progressive extension and bone erosion.

Introduction: Intradiploic pseudomeningoceles, also called intradiploic cerebrospinal fluid (CSF) fistulas, are abnormal CSF collections between the two bony tables of the calvaria resulting from postsurgical CSF leakage. To date, only six cases of intradiploic pseudomeningocele have been reported, all occurring in the occipital area. In this paper, we report the seventh case of late-onset occipital intradiploic pseudomeningocele (OIP) occurring in a young female patient who underwent surgery for the removal of a cerebellar pilocytic astrocytoma. In this regard, we also review the literature on the few recognized cases of OIP. Case Presentation: The case of an 18-year-old female patient known to our institute for an operation 12 years earlier to remove a pilocytic astrocytoma is illustrated. At admission, the patient complained only of occasional orthostatic headache. Brain imaging demonstrated a pseudomeningocele extended intradiploically from the occipital squama to the condylar and clivus regions, thinning both occipital bone tables and dilating the CSF-filled diploe. Watertight duroplasty and cranioplasty were effectively performed. Conclusion: Pediatric patients undergoing posterior cranial fossa craniotomy/craniectomy may postoperatively develop OIP. In this setting, treatment of any dural CSF fistula should be considered because of the risk of progressive extension and bone erosion.

We discuss C-MP and C-MAPF, generalizations of the classical Motion Planning (MP) and Multi-Agent Path Finding (MAPF) problems on a directed graph G. Namely, we enforce an upper bound on the number of agents that occupy each member of a family of vertex subsets. For instance, this constraint allows maintaining a safety distance between agents. We prove that finding a feasible solution of C-MP and C-MAPF is NP-hard, and we propose a reduction method to convert them to standard MP and MAPF. This reduction method consists in finding a subset of nodes W and a reduced graph G/W, such that a solution of MAPF on G/W provides a solution of C-MAPF on G. Moreover, we study the problem of finding W of maximum cardinality, which is strongly NP-hard.

On an assigned graph, the problem of Multi-Agent Pathfinding (MAPF) consists in finding paths for multiple agents, avoiding collisions. Finding the minimum-length solution is known to be NP-hard, and computation times grows exponentially with the number of agents. However, in industrial applications, it is important to find feasible, suboptimal solutions, in a time that grows polynomially with the number of agents. Such algorithms exist for undirected and biconnected directed graphs. Our main contribution is to generalize these algorithms to the more general case of strongly connected directed graphs. In particular, given a MAPF problem with at least two holes, we present an algorithm that checks the problem feasibility in linear time with respect to the number of nodes, and provides a feasible solution in polynomial time.

Cancer metabolism, including in mitochondria, is a disease hallmark and therapeutic target, but its regulation is poorly understood. Here, we show that many human tumors have heterogeneous and often reduced levels of Mic60, or Mitofilin, an essential scaffold of mitochondrial structure. Despite a catastrophic collapse of mitochondrial integrity, loss of bioenergetics, and oxidative damage, tumors with Mic60 depletion slow down cell proliferation, evade cell death, and activate a nuclear gene expression program of innate immunity and cytokine/chemokine signaling. In turn, this induces epithelial-mesenchymal transition (EMT), activates tumor cell movements through exaggerated mitochondrial dynamics, and promotes metastatic dissemination in vivo. In a small-molecule drug screen, compensatory activation of stress response (GCN2) and survival (Akt) signaling maintains the viability of Mic60-low tumors and provides a selective therapeutic vulnerability. These data demonstrate that acutely damaged, "ghost" mitochondria drive tumor progression and expose an actionable therapeutic target in metastasis-prone cancers.

Background: For a long time, surgery of insular gliomas was considered at high risk for postoperative cognitive deficits, but recent studies highlighted the feasibility of the surgical approach. The aims of our study were to investigate the presence of language impairment before and after surgery and the relationship between language impairment and tumor volume preoperatively and extent of resection (EOR) 3 months after surgery. Methods: Thirty-five patients with insular gliomas underwent an extensive language assessment before and few days after surgery, and after 3 months. Intraoperative neurophysiological monitoring (IOM) and brain mapping with direct electrical stimulation (DES) were used in all the cases; 8 patients underwent awake craniotomy. Statistical analysis was performed on the language tests administered. Results: Patients with pure left insular lesion showed language impairment before and after surgery. Overall, patients with a left lesion showed a drop of performance after surgery followed by a partial recovery. Moreover, when the tumor involved the insula and adjacent networks, we observed a more severe deficit. No correlations were found between tumor volume, EOR, and language impairment. Conclusions: Left insular lobe is an important hub in language networks; its involvement determines pre- and postsurgical deficits, together with the involvement of white matter connections. Tumor volume and EOR are not risk factors per se directly related to language functioning. Surgery of insular gliomas is possible with a pre- and intraoperative extensive study of the patient with IOM and awake surgery, and encouraged by the trend of cognitive recovery highlighted.

The purpose of this work is to introduce and characterize the Bounded Acceleration Shortest Path (BASP) problem, a generalization of the Shortest Path (SP) problem. This problem is associated to a graph: the nodes represent positions of a mobile vehicle and the arcs are associated to pre-assigned geometric paths that connect these positions. BASP consists in finding the minimum-time path between two nodes. Differently from SP, we require that the vehicle satisfy bounds on maximum and minimum acceleration and speed, that depend on the vehicle position on the currently traveled arc. We prove that BASP is NP-hard and define solution algorithm that achieves polynomial time-complexity under some additional hypotheses on problem data., Comment: 39 pages

In this paper we propose a variant of the linear least squares model allowing practitioners to partition the input features into groups of variables that they require to contribute similarly to the final result. The output allows practitioners to assess the importance of each group and of each variable in the group. We formally show that the new formulation is not convex and provide two alternative methods to deal with the problem: one non-exact method based on an alternating least squares approach; and one exact method based on a reformulation of the problem using an exponential number of sub-problems whose minimum is guaranteed to be the optimal solution. We formally show the correctness of the exact method and also compare the two solutions showing that the exact solution provides better results in a fraction of the time required by the alternating least squares solution (assuming that the number of partitions is small). For the sake of completeness, we also provide an alternative branch and bound algorithm that can be used in place of the exact method when the number of partitions is too large, and a proof of NP-completeness of the optimization problem introduced in this paper.

Circulating platelets (PLTs) are able to affect glioblastoma (GBM) microenvironment by supplying oncopromoter and pro-angiogenic factors. Among these mediators, sphingosine-1-phophate (S1P) has emerged as a potent bioactive lipid enhancing cell proliferation and survival. Here, we investigated the effect of “tumor education”, characterizing PLTs from GBM patients in terms of activation state, protein content, and pro-angiogenic potential. PLTs from healthy donors (HD-PLTs) and GBM patients (GBM-PLTs) were collected, activated, and analyzed by flow cytometry, immunofluorescence, and Western blotting. To assess the pro-angiogenic contribution of GBM-PLTs, a functional cord formation assay was performed on GBM endothelial cells (GECs) with PLT-releasate. GBM-PLTs expressed higher positivity for P-selectin compared to HD-PLTs, both in basal conditions and after stimulation with adenosine triphosphate (ADP) and thrombin receptor activating peptide (TRAP). PLTs showed higher expression of VEGFR-1, VEGFR-2, VWF, S1P, S1PR1, SphK1, and SPNS. Interestingly, increased concentrations of VEGF and its receptors VEGFR1 and VEGFR2, VWF, and S1P were found in GBM-PLT-releasate with respect to HD-PLTs. Finally, GBM-PLT-releasate showed a pro-angiogenic effect on GECs, increasing the vascular network’s complexity. Overall, our results demonstrated the contribution of PLTs to GBM angiogenesis and aggressiveness, advancing the potential of an anti-PLT therapy and the usefulness of PLT cargo as predictive and monitoring biomarkers.

The problem of planar registration consists in finding the transformation that better aligns two point sets. In our setting, the search domain is the set of planar rigid transformations and the objective function is the sum of the distances between each point of the transformed source set and the destination set. We consider a Branch and Bound (BnB) method for finding the globally optimal solution. The algorithm recursively splits the search domain into boxes and computes an upper and a lower bound for the minimum value of the restricted problem. The main contribution of this work is the introduction of a novel lower bound, the relaxation bound, which corresponds to the solution of a concave relaxation of the objective function based on the linearization of the distance. In the BnB we also employ the so called cheap bound, equal to to the sum of the minimum distances between each point of source point set, transformed according to current box, and all the candidate points in the destination point set. We prove, both theoretically and practically, that the novel relaxation bound dominates the cheap bound over small boxes. More precisely, from the theoretical point of view, we prove that the relaxation bound is a second-order approximation of the minimum value, i.e., its distance from the minimum value decreases quadratically with respect to the diameter of the box (see Theorem 1), while the cheap bound is a first-order one (see Proposition 3). From the practical point of view, we show through different computational experiments that the addition of the relaxation bound considerably enhances the performance of the BnB algorithm, compensating the higher cost of its computation with respect to the cheap bound with a strong reduction of the number of BnB nodes to be explored., Comment: 40 pages, 13 figures, 2 tables

This thesis seeks to better understand how a combination of different project management approaches could lead organisations to cope with project closure in more effective ways. More specifically, a coexistence of Waterfall and Agile project management is examined and presented as positive contribution to insurance and investment organisations for more effective transitions from project management to business-as-usual. A comprehensive framework combines within the theoretical chapters the hybrid approach between Agile and traditional project management for successfully closing projects. It represents the lens through which the empirical material can be analysed.The empirical work is based on a single-holistic case study of Intesa Sanpaolo Life dac, incorporating seven semi-structured interviews with the most authoritative individuals of this company in relation to the topic of this paper. This case study provides a deep insight on project closure management which is addressed by investigating challenges and highlighting effective practices of the company in question. Throughout the analysis of the data gathered, the authors managed to highlight findings which provide managerial and theoretical contributions.The originality and the value of this research is given by the fact that this work expects to enrich project-based organisations which use a combination between Agile and traditional project management and struggle to get a proper project closure and transit to the operation phase. Consequently, this represents a completely new point of view in the literature related to project management, which sees project closure as the most understudied phase of the project life-cycle.

The authors present an unusual case of a patient suffering from visual deficit due to pituitary granulomatosis with polyangiitis (GPA) associated with Rathke's cleft cyst (RCC). The patient was referred to our Neurosurgery Department presenting right eye amaurosis, third cranial nerve palsy, and left temporal hemianopsia. Magnetic resonance imaging documented a sellar or suprasellar lesion with solid and cystic components. The dura mater of the skull base was also strongly enhanced. The patient underwent surgery. Histologic examination revealed RCC associated with pituitary GPA. To our knowledge, this is the first reported case of concomitant pituitary GPA and RCC. Pituitary involvement in GPA is rare, usually diagnosed in hormonal dysfunctions. The patient in case first presented optic chiasm compression, probably due to inflammation of both the pituitary gland and the previously asymptomatic RCC. We focus on the symptoms that led us to diagnose GPA pituitary involvement and on the peculiar and unusual Magnetic resonance imaging of the case presented.

Surgical treatment of elderly patients with meningioma is has proved to be safe, especially when patients are selected using dedicated surgical scores. These scores take into account tumor size, edema, location and patient’s co-morbidities. Neuropsychological functioning (NPF) of this kind of patients has been poorly studied in literature and it is not taken into account by these scores. Aim of our study was to describe the long-term outcome in terms of NPF of elderly patients undergoing surgery. Patients older than 70 years of age affected by intracranial meningioma and selected with the Clinical-Radiological Grading Score were included in our study. Neuropsychological testing was performed using a dedicated battery of tests before surgery, 3 and 12 months after surgery. Clinical, neurological and radiological outcomes were studied as well. Forty-one patients with a median age of 74 years were included in this study. Preoperatively only 1/41 patients showed a normal NPF with all tests scoring normally. Four out of 39 patients showed a complete neuropsychological recovery after 3 months; while 10/37 patients had a complete recovery after 12 months. NPF showed a trend of progressive improvement after surgery. Our study is the first experience reported in literature describing a long term follow-up in elderly patients after surgery for intracranial meningioma. In our series, surgery determined an improvement of NPF over time; especially with a low complication rate related to the selection of patients obtained through the CRGS. Further studies need to be performed in order to understand how brain edema, tumor size, volume and tumor location affect NPF in both short and long term.

This thesis seeks to better understand how a combination of different project management approaches could lead organisations to cope with project closure in more effective ways. More specifically, a coexistence of Waterfall and Agile project management is examined and presented as positive contribution to insurance and investment organisations for more effective transitions from project management to business-as-usual. A comprehensive framework combines within the theoretical chapters the hybrid approach between Agile and traditional project management for successfully closing projects. It represents the lens through which the empirical material can be analysed.The empirical work is based on a single-holistic case study of Intesa Sanpaolo Life dac, incorporating seven semi-structured interviews with the most authoritative individuals of this company in relation to the topic of this paper. This case study provides a deep insight on project closure management which is addressed by investigating challenges and highlighting effective practices of the company in question. Throughout the analysis of the data gathered, the authors managed to highlight findings which provide managerial and theoretical contributions.The originality and the value of this research is given by the fact that this work expects to enrich project-based organisations which use a combination between Agile and traditional project management and struggle to get a proper project closure and transit to the operation phase. Consequently, this represents a completely new point of view in the literature related to project management, which sees project closure as the most understudied phase of the project life-cycle.

We consider the speed planning problem for a robotic manipulator. In particular, we present an algorithm for finding the time-optimal speed law along an assigned path that satisfies velocity and acceleration constraints and respects the maximum forces and torques allowed by the actuators. The addressed optimization problem is a finite dimensional reformulation of the continuous-time speed optimization problem, obtained by discretizing the speed profile with N points. The proposed algorithm has linear complexity with respect to N and to the number of degrees of freedom. Such complexity is the best possible for this problem. Numerical tests show that the proposed algorithm is significantly faster than algorithms already existing in literature.

BACKGROUND AND PURPOSE: Cerebral cavernous malformation (CCM) is characterized by multiple lumen vascular malformations in the central nervous system that can cause neurological symptoms and brain hemorrhages. About 20% of CCM patients have an inherited form of the disease with ubiquitous loss-of-function mutation in any one of 3 genes CCM1, CCM2, and CCM3. The rest of patients develop sporadic vascular lesions histologically similar to those of the inherited form and likely mediated by a biallelic acquired mutation of CCM genes in the brain vasculature. However, the molecular phenotypic features of endothelial cells in CCM lesions in sporadic patients are still poorly described. This information is crucial for a targeted therapy. METHODS: We used immunofluorescence microscopy and immunohistochemistry to analyze the expression of endothelial-to-mesenchymal transition markers in the cavernoma of sporadic CCM patients in parallel with human familial cavernoma as a reference control. RESULTS: We report here that endothelial cells, a cell type critically involved in CCM development, undergo endothelial-to-mesenchymal transition in the lesions of sporadic patients. This switch in endothelial phenotype has been described only in genetic CCM patients and in murine models of the disease. In addition, TGF-β/p-Smad- and β-catenin-dependent signaling pathways seem activated in sporadic cavernomas as in familial ones. CONCLUSIONS: Our findings support the use of common therapeutic strategies for both sporadic and genetic CCM malformations., Dejana E and Lampugnani MG share the last authorship.

Hypoxia is a universal driver of aggressive tumor behavior, but the underlying mechanisms are not completely understood. Using a phosphoproteomics screen, we now show that active Akt accumulates in the mitochondria during hypoxia and phosphorylates pyruvate dehydrogenase kinase 1 (PDK1) on Thr346 to inactivate the pyruvate dehydrogenase complex. In turn, this pathway switches tumor metabolism toward glycolysis, antagonizes apoptosis and autophagy, dampens oxidative stress, and maintains tumor cell proliferation in the face of severe hypoxia. Mitochondrial Akt-PDK1 signaling correlates with unfavorable prognostic markers and shorter survival in glioma patients and may provide an "actionable" therapeutic target in cancer.

Valuable documents are included in the corpus of information, documentation, digital contents produced in the course of projects aimed at studying and defining a preservation (and possibly restoration) plan for a significant piece of cultural heritage. These documents could be exploited to effectively further valorize the cultural heritage and support its fruition by a wide audience of potential users. The TIVal project aims at supporting the integration of this kind of different, distinct and heterogeneous multimedia contents into a comprehensive and accessible portal. The latter proposes specific navigation paths, dynamically connecting the different contents according to a specific logical rationale of the path itself (e.g. show information supporting a critical analysis of a piece of cultural heritage). To support the dynamic creation of these paths, contents are organized by means of the adoption of a domain ontology derived from CIDOC CRM. The paper presents the rationale of the approach, the architecture of the system, the structure of the ontology, and relevant examples of its usage by specific navigation paths.

This paper focuses on tight communities and specifically on the distributed, mediated discourses that their members articulate around documents and inscribed material artifacts. The paper presents a prototype-based design experience toward the definition of a collaborative annotation tool that is endowed with discourse oriented functionalities whose main characteristics have emerged from case studies we undertook in the healthcare and agricultural domains. In latter domain an initial prototype was proposed and progressively tuned to help users propose modifications to an institutional document through the expression of comments gathered around and about a common artifact, and then build a representative summary of the opinions emerging within the community as a result of this distributed discussion. In light of the reported case study, we discuss a new perspective on this class of annotating applications and the related functionalities that could realize a new simplified model of discourse and foster its adoption in distributed settings and communities of practice

Valuable documents are included in the corpus of information, documentation, digital contents produced in the course of projects aimed at studying and defining a preservation (and possibly restoration) plan for a significant piece of cultural heritage. These documents could be exploited to effectively further valorize the cultural heritage and support its fruition by a wide audience of potential users. The TIVal project aims at supporting the integration of this kind of different, distinct and heterogeneous multimedia contents into a comprehensive and accessible portal. The latter proposes specific navigation paths, dynamically connecting the different contents according to a specific logical rationale of the path itself (e.g. show information supporting a critical analysis of a piece of cultural heritage). To support the dynamic creation of these paths, contents are organized by means of the adoption of a domain ontology derived from CIDOC CRM. The paper presents the rationale of the approach, the architecture of the system, the structure of the ontology, and relevant examples of its usage by specific navigation paths.

The paper introduces an architectural model, which pairs virtual and physical ecologies into augmented ecologies. The notion of space as a first class concept fosters a neat separation of the two main parts of an ecology: the environment and the organisms it contains. Virtual organisms view the common environment through multiple ecology spaces, described in terms of core space models and related by mappings between locations. This leads to a flexible space-aware paradigm supporting the indirect communication between organisms, including both message passing and data sharing. Finally, the paper presents a concrete framework reifying the model and an example application.

The highly distributed cooperation that characterizes several domain, like healthcare, collaborative design and cultural resources management, often raise coordination conflicts and collaborative problems. These problems require a suitable technological support that can make the members of the groups involved in these collaborative practices aware of the crucial information that is generated in the other groups. In this paper, we propose a framework for the design of such technological supports and illustrate its application by means of an articulated healthcare scenario. Our framework allows users to: manage the creation and execution of rules that are specific and “local” to specific groups; manage the exchange of rules, and hence of “procedural knowledge”, across and among different groups; conceive predefined procedures that are considered as “carriers” of contextual information rather than models of prescriptive behavior; become mutually aware of interdependent task articulation as a basic support of inter-group collaboration; get facilitated access to the relevant information that supports their collaborative activities.

The highly distributed cooperation that characterizes several domain, like healthcare, collaborative design and cultural resources management, often raise coordination conflicts and collaborative problems. These problems require a suitable technological support that can make the members of the groups involved in these collaborative practices aware of the crucial information that is generated in the other groups. In this paper, we propose a framework for the design of such technological supports and illustrate its application by means of an articulated healthcare scenario. Our framework allows users to: manage the creation and execution of rules that are specific and “local” to specific groups; manage the exchange of rules, and hence of “procedural knowledge”, across and among different groups; conceive predefined procedures that are considered as “carriers” of contextual information rather than models of prescriptive behavior; become mutually aware of interdependent task articulation as a basic support of inter-group collaboration; get facilitated access to the relevant information that supports their collaborative activities.

Archaeology is a domain of work where photographs play a relevant role: here they are used in different phases of the archaeological work for many purposes, some of which are common to other domains or to home usage (e.g., archiving). We focus our attention on one of the initial phases of the archaeological process, namely excavation, since the related activities use photographs in a very particular way and under the constraints of a very demanding physical setting. Moreover, in this phase the use of digitized photographs is recent, and in their adoption they are interestingly combined with photographs printed on paper. This paper presents the results of a study performed at an archaeological site in the south of Italy: it reports the observed collocated collaborative practices surrounding photographs and discusses these practices to identify some functionalities of a supportive technology. © Springer 2011.

In this paper we define a discrete dynamical system that governs the evolution of a population of agents. From the dynamical system, a variant of Differential Evolution is derived. It is then demonstrated that, under some assumptions on the differential mutation strategy and on the local structure of the objective function, the proposed dynamical system has fixed points towards which it converges with probability one for an infinite number of generations. This property is used to derive an algorithm that performs better than standard Differential Evolution on some space trajectory optimization problems. The novel algorithm is then extended with a guided restart procedure that further increases the performance, reducing the probability of stagnation in deceptive local minima., Comment: IEEE Transactions on Evolutionary Computation 2011. ISSN 1089-778X

Given the international interest, debate and controversy on questions of the subaltern classes and of relationships of hegemony, it has been thought useful to present here a number of sections (conventionally called paragraphs) from the Prison Notebooks that are as yet awaiting publication in an English translation. They will of course come out in Joseph Buttigieg’s ongoing project of the translation in their entirety of the Gerratana edition of the Notebooks, and publication of some of Gramsci’s first drafts of the pieces here included are imminent. In other cases, however, the first drafts by Gramsci, especially the paragraphs discussing Ettore Ciccotti’s articles, have actually been published in the second volume of the Buttigieg edition,1 not to mention of course editions in languages other than English. Apart from Gramsci’s general discussion of the emergence of the subaltern classes and their struggle for recognition and even some sort of hegemony, what readers may find of further interest is the way in which he reworks and elaborates his arguments either in detail or at the level of what often appear relatively minor specifications.

Given the international interest, debate and controversy on questions of the subaltern classes and of relationships of hegemony, it has been thought useful to present here a number of sections (conventionally called paragraphs) from the Prison Notebooks that are as yet awaiting publication in an English translation. They will of course come out in Joseph Buttigieg’s ongoing project of the translation in their entirety of the Gerratana edition of the Notebooks, and publication of some of Gramsci’s first drafts of the pieces here included are imminent. In other cases, however, the first drafts by Gramsci, especially the paragraphs discussing Ettore Ciccotti’s articles, have actually been published in the second volume of the Buttigieg edition,1 not to mention of course editions in languages other than English. Apart from Gramsci’s general discussion of the emergence of the subaltern classes and their struggle for recognition and even some sort of hegemony, what readers may find of further interest is the way in which he reworks and elaborates his arguments either in detail or at the level of what often appear relatively minor specifications.

A domain where photographs are a necessary part is archaeology: here they are used in different phases of the archaeological work for many purposes, some of which are common to other domains or to home usage (e.g., archiving). We concentrate our attention one of the initial phases of the archaeological process, namely excavation, since the related activities use photographs in a very peculiar way and under the constraints of a very demanding physical setting. Moreover, in this phase the advent of digitalized photographs is recent and their adoption is still interestingly combined with the usage of photographs printed on paper. Paper presents the results of a study performed at an archaeological site in the south of Italy: we report the observed collocated collaborative practices surrounding photos and discuss these practices to identify some functionality of a supportive technology

The paper proposes an approach to EUD focusing on communities: on the one hand, users are considered as a community of cooperating actors; on the other hand, applications and devices are considered as a (artificial) community that, by interacting with those actors, cooperate to support their collaboration. This idea facilitates an integration based on modularization and abstraction, by applying to the technology principles that are derived from human collaboration: in so doing, it others a uniform approach that allows users with different technical capabilities to operate at different levels of abstraction by applying the same conceptual tools. The community metaphor inspires a model that helps the users community integrating devices and applications according to its needs. In turn, the model defines a layered structure of primitives: from the basic ones up to the domain and application dependent ones, passing through the domain and application independent primitives. The approach is illustrated by an example in the education domain: the interaction flows in an augmented classroom can be defined and adapted by communities where teachers, tutors and students organize their collaboration.

This paper presents an agent-based approach to the modeling, design and engineering of ambient intelligence systems. The introduced approach balances the management of the complexity related to the enactment of an ambient intelligence scenario between the agents and the structured environment they populate. The dynamics of local actions and interactions of agents situated in this environment originates the overall organized system behaviour. The environment is shaped according to the notion of active coordination artifact, whose seminal definition was given in Computer Supported Cooperative Work literature by Schmidt and Simone and then evolved in other research contexts. A technique to configure and interact with such environments, i.e. the composition of device functionalities according to their high-level features, and services provided, is presented. A scenario is used as an in-depth example, and the architecture of a sample system implementing the same scenario using our reference middleware is discussed. © The Author 2008. Published by Oxford University Press on behalf of The British Computer Society. All rights reserved.

The paper shows how a pervasive computing architecture, CASMAS, and its associated modelling language can be used to support cooperation among the members of a patient-centred community of care and their digital devices. We also show how CASMAS can be augmented by the WOAD framework, which was developed independently to model and express declarative mechanisms of provision of awareness promoting information (API) in document-mediated communities. Parts of these mechanisms can be modelled on the basis of integrated care pathways taken from the medical specialist literature. We take the distributed hypertension monitoring case as an exemplifying and sufficiently complex scenario to show the feasibility and advantages of our semantically informed and modular approach. The scenario is then declined in terms of architectural components and cooperation-oriented mechanisms that are shared between the devices and entities of the designed community of care.

This paper describes an integrated approach to the valorization of cultural heritage and its application in the context of the “Milano Antica” (Ancient Milan) project, whose aim is the development of an integrated access to information on the archaeological heritage of the city of Milan in its historical period called “Ancient City” (V century B.C. - VI century A.D.). The scenario is characterized by distinct research and preservation activities, abundant and heterogenous results, materials, information and documents. To face the challenges related to the realization of a uniform access point to the relevant information we adopted the CIDOC CRM, a standard and open conceptual and computational model for the description of Cultural Heritage.

In this paper, we present an ubiquitous and pervasive computing architecture, CASMAS, aimed at supporting cooperation among the members of a community and their devices. We also show how CASMAS can be augmented by the WOAD framework, which was developed independently to model and express coordination mechanisms in document-mediated communities. We take the distributed hypertension monitoring case as an exemplifying and sufficiently complex scenario to show the feasibility and advantages of the our semantically informed modular approach. The scenario is then declined in terms of architectural components and cooperation-oriented mechanisms that are shared between the devices and entities of the designed community of care.

All personal computer application are provided with an undo functionality, which can implement any of the models available in literature. Users are generally aware of what the undo function is expected to do, depending on the application in use. Ubiquitous computing systems are beginning to be understood and deployed in real life situations, but little attention has been paid to what users expect themselves to be able to do and undo in such systems. In this paper, we present the results of a survey we made to evaluate the perception of undo mechanisms with respect to a simple ubiquitous-computing environment. Our study shows that users already have a complex vision of undo encompassing advanced features such as context awareness and compensation. © 2008 Springer-Verlag Berlin Heidelberg.

Besides technological challenges, there is a growing interest on how pervasive computing can deeply affect the way in which people interact and accomplish collaborative tasks. Context awareness plays a crucial role for communities, where the degree of participation of a single user dynamically changes in relation to the distance from the place where practices occur and in relation with the ability of gathering the right information at the right time, and in a proper way. In this paper, we adopt an interpretation of pervasive computing as an environment, populated by interconnected smart devices, where users can interact with each other, individually or in groups, to accomplish collaborative tasks. In other words, we aim at modeling, designing and realizing Collaborative Ubiquitous Environments (CUEs). We present an agent based model, balancing the management of such a complex scenario between agents and a structured multifaceted environment.

A comprehensive approach to the design of Ubiquitous Computing systems must deal with the issues related to the restoration of an earlier or acceptable state of the system, if possible, when users intentionally want to undo some previous actions. Systems supporting collaborative Ubiquitous Computing environments should provide a default undo function, but also provide users and applications with awareness information to correctly decide which (compensative) actions should be undertaken. In this paper we describe how to achieve undo in distributed, dynamic, context-aware systems. We present a general approach to undo in collaborative Ubiquitous Computing environments in terms of the CASMAS model: part of the approach relies on the notion of active coordination artifacts, as defined also in CSCW literature. © 2008 Springer-Verlag Berlin Heidelberg.

Collaborative Ubiquitous Environments (CUEs) are environments supporting collaboration among persons in a ubiquitous computing setting. This paper shows how results of the research in the Multi-Agent System (MAS) area, and in particular on MAS environments, can be used to model, design and engineer CUEs, with specific reference to the management of context-awareness information. The CUE reference scenario will be introduced, then the Multilayered Multi-Agent Situated System model will be briefly described and applied to represent and to manage several types of awareness information (both physical and logical contextual information). Finally, the paper introduces a prototypal framework based on DJess supporting the definition and management of MMASS based CUEs.

Coordination artifacts play a primary role in cooperation and, in particular, active artifacts allow for the development of flexible cooperative software systems. Their role with respect to ubiquitous-computing environments can be defined, exploited, and assessed according to different perspectives. This paper presents a notion of active artifact that relies on the seminal definition given in CSCW literature by Schmidt and Simone, and it is applied to a model for systems supporting ubiquitous-computing collaborative environments (CASMAS). A technique to configure and interact with such environments, i.e., the composition of devices' functionalities according to their high-level features, and services provided, is presented. A scenario is used as an in-depth example along the paper. The architecture of a system implementing the scenario using our reference middleware is presented

Collaborative Ubiquitous Environments (CUEs) are environments that support collaboration among persons in a context of ubiquitous computing. This article shows how results of the research in the Multi-Agent System (MAS) area, and in particular on MAS environments, can be used to model, design and engineer CUEs, with specific reference to the management of context-awareness information. After a description of the reference scenario, the Multilayered Multi-Agent Situated System model will be introduced and applied to represent and to manage several types of awareness information (both physical and logical contextual information). Finally, three different approaches to the design and engineering of CUEs will then be introduced and evaluated. © 2007 ACM.