2,006 research outputs found
Tracking advanced persistent threats in critical infrastructures through opinion dynamics
Advanced persistent threats pose a serious issue for modern industrial environments, due to their targeted and complex attack vectors that are difficult to detect. This is especially severe in critical infrastructures that are accelerating the integration of IT technologies. It is then essential to further develop effective monitoring and response systems that ensure the continuity of business to face the arising set of cyber-security threats. In this paper, we study the practical applicability of a novel technique based on opinion dynamics, that permits to trace the attack throughout all its stages along the network by correlating different anomalies measured over time, thereby taking the persistence of threats and the criticality of resources into consideration. The resulting information is of essential importance to monitor the overall health of the control system and cor- respondingly deploy accurate response procedures. Advanced Persistent Threat Detection Traceability Opinion Dynamics.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
In-depth analysis of the Naming Game dynamics: the homogeneous mixing case
Language emergence and evolution has recently gained growing attention
through multi-agent models and mathematical frameworks to study their behavior.
Here we investigate further the Naming Game, a model able to account for the
emergence of a shared vocabulary of form-meaning associations through
social/cultural learning. Due to the simplicity of both the structure of the
agents and their interaction rules, the dynamics of this model can be analyzed
in great detail using numerical simulations and analytical arguments. This
paper first reviews some existing results and then presents a new overall
understanding.Comment: 30 pages, 19 figures (few in reduced definition). In press in IJMP
Note and Comment
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Sharp transition towards shared vocabularies in multi-agent systems
What processes can explain how very large populations are able to converge on
the use of a particular word or grammatical construction without global
coordination? Answering this question helps to understand why new language
constructs usually propagate along an S-shaped curve with a rather sudden
transition towards global agreement. It also helps to analyze and design new
technologies that support or orchestrate self-organizing communication systems,
such as recent social tagging systems for the web. The article introduces and
studies a microscopic model of communicating autonomous agents performing
language games without any central control. We show that the system undergoes a
disorder/order transition, going trough a sharp symmetry breaking process to
reach a shared set of conventions. Before the transition, the system builds up
non-trivial scale-invariant correlations, for instance in the distribution of
competing synonyms, which display a Zipf-like law. These correlations make the
system ready for the transition towards shared conventions, which, observed on
the time-scale of collective behaviors, becomes sharper and sharper with system
size. This surprising result not only explains why human language can scale up
to very large populations but also suggests ways to optimize artificial
semiotic dynamics.Comment: 12 pages, 4 figure
Advancing integrative âone-healthâ approaches to global health through multidisciplinary, faculty-led global health field courses
AbstractBackgroundSince 2003, the University of Wisconsin-Madison Global Health Institute, together with collaborating campus and in-country partners, has offered immersive, multidisciplinary, faculty-led, global health field courses in Ecuador and Thailand. These courses aim to help students to develop a working understanding of integrative one-health approaches and acquire the skills to work effectively across disciplines. That is, we aim to foster an appreciation of the role of culture in perceptions of health, disease, and health care; the complex interactions of animal-human-ecosystem health and disease; and the value of integrating cross-disciplinary and cross-cultural perspectives and skills to solve complex public health problems.MethodsStudents from various University of Wisconsin-Madison health faculties travelled, lived (accommodation included homestays in indigenous or rural communities), learnt, and engaged in community-health assessments or service-learning projects as a multidisciplinary team. We recruited students through annual presentations in each University of Wisconsin school or college and through recommendations from past participants. We recorded student reflections during the course, at course completion, and after graduation.FindingsBetween 2003 and 2014: 215 students from the University of Wisconsin have taken part in the global health field courses. Students came from the fields of human medicine (53 [25%]), veterinary medicine (35 [16%]), nursing (40 [19%]), pharmacy (41 [19%]), and other degree programs (46 [21%]). Results of the in-course and post course assessments consistently show strong student satisfaction with many aspects of the programme, including safety, faculty mentorship, the value of the multidisciplinary approach, depth of learning, and programme cost. Former participants also report use of cross-cultural skills in their professional practice, work with populations from cultures other than their own, positive effects on their decisions for career activities, and the belief that immersive cross-cultural experiences should be a required part of professional training for all health professional students. Finally, the courses undergo independent programme evaluations (including in-country observation and interviews with participants and stakeholders) approximately every 5 years.InterpretationProgramme directors continue to seek improvements related to: sustainable faculty engagement from various disciplines; development of increasingly specific course group learning objectives, competencies, and assessment tools; sustainability of impacts on community-level health and wellbeing; continuity between University of Wisconsin-Madison and in-country university and community partners; and scholarship support and other approaches so that cost does not exclude interested students from participating.FundingThe GHI is supported through a combination of university, grants, and philanthropic funding; these field courses do not have specific, separate funding. Students self-fund participation in the courses
A Framework to Manage the Complex Organisation of Collaborating: Its Application to Autonomous Systems
In this paper we present an analysis of the complexities of large group
collaboration and its application to develop detailed requirements for
collaboration schema for Autonomous Systems (AS). These requirements flow from
our development of a framework for collaboration that provides a basis for
designing, supporting and managing complex collaborative systems that can be
applied and tested in various real world settings. We present the concepts of
"collaborative flow" and "working as one" as descriptive expressions of what
good collaborative teamwork can be in such scenarios. The paper considers the
application of the framework within different scenarios and discuses the
utility of the framework in modelling and supporting collaboration in complex
organisational structures
Multiâscale heterogeneity in vegetation and soil carbon in exurban residential land of southeastern Michigan, USA
Exurban residential land (one housing unit per 0.2â16.2 ha) is growing in importance as a humanâdominated land use. Carbon storage in the soils and vegetation of exurban land is poorly known, as are the effects on C storage of choices made by developers and residents. We studied C storage in exurban yards in southeastern Michigan, USA, across a range of parcel sizes and different types of neighborhoods. We divided each residential parcel into ecological zones (EZ) characterized by vegetation, soil, and human behavior such as mowing, irrigation, and raking. We found a heterogeneous mixture of trees and shrubs, turfgrasses, mulched gardens, oldâfield vegetation, and impervious surfaces. The most extensive zone type was turfgrass with sparse woody vegetation (mean 26% of parcel area), followed by dense woody vegetation (mean 21% of parcel area). Areas of turfgrass with sparse woody vegetation had trees in larger size classes (> 50 cm dbh) than did areas of dense woody vegetation. Using aerial photointerpretation, we scaled up C storage to neighborhoods. Varying C storage by neighborhood type resulted from differences in impervious area (8â26% of parcel area) and area of dense woody vegetation (11â28%). Averaged and multiplied across areas in differing neighborhood types, exurban residential land contained 5240 ± 865 g C/m2 in vegetation, highly sensitive to large trees, and 13 800 ± 1290 g C/m2 in soils (based on a combined sampling and modeling approach). These contents are greater than for agricultural land in the region, but lower than for mature forest stands. Compared with mature forests, exurban land contained more shrubs and less downed woody debris and it had similar tree sizeâclass distributions up to 40 cm dbh but far fewer trees in larger size classes. If the trees continue to grow, exurban residential land could sequester additional C for decades. Patterns and processes of C storage in exurban residential land were driven by land management practices that affect soil and vegetation, reflecting the choices of designers, developers, and residents. This study provides an example of humanâmediated C storage in a coupled humanânatural system.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/122437/1/eap1313.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/122437/2/eap1313_am.pd
Global alterations to the choroid plexus blood-CSF barrier in amyotrophic lateral sclerosis
© 2020 The Author(s). The choroid plexus (CP) is a highly vascularized structure located in the ventricles that forms the blood-CSF barrier (BCSFB) and separates the blood from the cerebrospinal fluid (CSF). In addition to its role as a physical barrier, the CP functions in CSF secretion, transport of nutrients into the central nervous system (CNS) and a gated point of entry of circulating immune cells into the CNS. Aging and neurodegeneration have been reported to affect CP morphology and function and increase protein leakage from blood to the CSF. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease associated with both upper and lower motor neuron loss, as well as altered proteomic and metabolomic signatures in the CSF. The role of the BCSFB and the CP in ALS is unknown. Here we describe a transcriptomic and ultrastructural analysis of BCSFB and CP alterations in human postmortem tissues from ALS and non-neurologic disease controls. ALS-CP exhibited widespread disruptions in tight junctional components of the CP epithelial layer and vascular integrity. In addition, we detected loss of pericytes around ALS blood vessels, accompanied by activation of platelet aggregation markers vWF and Fibrinogen, reminiscent of vascular injury. To investigate the immune component of ALS-CP, we conducted a comprehensive analysis of cytokines and chemokine panels in CP lysates and found a significant down-regulation of M-CSF and V-CAM1 in ALS, as well as up-regulation of VEGF-A protein. This phenotype was accompanied by an infiltration of MERTK positive macrophages into the parenchyma of the ALS-CP when compared to controls. Taken together, we demonstrate widespread structural and functional disruptions of the BCSFB in human ALS increasing our understanding of the disease pathology and identifying potential new targets for ALS therapeutic development
Iron biogeochemistry across marine systems progress from the past decade
Based on an international workshop (Gothenburg, 14â16 May 2008), this review article aims to combine interdisciplinary knowledge from coastal and open ocean research on iron biogeochemistry. The major scientific findings of the past decade are structured into sections on natural and artificial iron fertilization, iron inputs into coastal and estuarine systems, colloidal iron and organic matter, and biological processes. Potential effects of global climate change, particularly ocean acidification, on iron biogeochemistry are discussed. The findings are synthesized into recommendations for future research areas
Physicality and Cooperative Design
CSCW researchers have increasingly come to realize that material work setting and its population of artefacts play a crucial part in coordination of distributed or co-located work. This paper uses the notion of physicality as a basis to understand cooperative work. Using examples from an ongoing fieldwork on cooperative design practices, it provides a conceptual understanding of physicality and shows that material settings and co-workerâs working practices play an important role in understanding physicality of cooperative design
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