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51.
Daniela Ballari Monica Wachowicz Arnold K. Bregt Miguel Manso-Callejo 《Computers, Environment and Urban Systems》2012
Wireless sensor networks (WSNs) play an important role in forest fire risk monitoring. Various applications are in operation. However, the use of mobile sensors in forest risk monitoring remains largely unexplored. Our research contributes to fill this gap by designing a model which abstracts mobility constraints within different types of contexts for the inference of mobile sensor behaviour. This behaviour is focused on achieving a suitable spatial coverage of the WSN when monitoring forest fire risk. The proposed mobility constraint model makes use of a Bayesian network approach and consists of three components: (1) a context typology describing different contexts in which a WSN monitors a dynamic phenomenon; (2) a context graph encoding probabilistic dependencies among variables of interest; and (3) contextual rules encoding expert knowledge and application requirements needed for the inference of sensor behaviour. As an illustration, the model is used to simulate the behaviour of a mobile WSN to obtain a suitable spatial coverage in low and high fire risk scenarios. It is shown that the implemented Bayesian network within the mobility constraint model can successfully infer behaviour such as sleeping sensors, moving sensors, or deploying more sensors to enhance spatial coverage. Furthermore, the mobility constraint model contributes towards mobile sensing in which the mobile sensor behaviour is driven by constraints on the state of the phenomenon and the sensing system. 相似文献
52.
Marc Bescond Jean-Luc Autran Nicolas Cavassilas Daniela Munteanu Michel Lannoo 《Journal of Computational Electronics》2004,3(3-4):393-396
A program to numerically simulate point defects in nanowire metal-oxide-semiconductor field-effect transistors is described. The simulation scheme is based on the non-equilibrium Green’s function method self-consistently being obtained via the resolution of 3D Poisson’s equation. A tight-binding hamiltonian is used and the point defect is characterized by a macroscopic coulombic tail treated in the mode-space approach, plus a short range on-site perturbation potential energy, treated exactly. The effect on internal quantities and on the transistor characteristics is studied as a function of the strength and the location of the defect potential. Subthreshold current is found to vary in a factor 10 according to the position of the impurity.Also With Institut Universitaire De France (IUF). 相似文献
53.
Mayes Andrew R.; Montaldi Daniela; Spencer Tom J.; Roberts Neil 《Canadian Metallurgical Quarterly》2004,18(3):426
Activations produced by the recall of episodic and semantic memories differing in spatial content and age were examined. Recall of recent episodic memories with differing spatial content activated the medial temporal lobes and the retrosplenial-posterior cingulate cortex-precuneus complex more than recall of recent semantic memories with similarly differing spatial content. Some of these differences related to the amount of spatial information recalled because spatially richer recent memories, regardless of whether they were episodic or semantic, activated the right posterior parahippocampal cortex, precuneus, and posterior parietal cortex more. This spatial effect was found to be independent of memory age for semantic memories, although some episodic-semantic memory differences, including one in the left hippocampus, were not age independent. Episodic-semantic memory recall activation differences are therefore probably a function of the amount recalled, memory age, and what is recalled, particularly with respect to spatial information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
The paper is about some families of rewriting P systems, where the application of evolution rules is extended from the classical
sequential rewriting to the parallel one (as, for instance, in Lindenmayer systems). As a result, consistency problems for
the communication of strings may arise. Three variants of parallel rewriting P systems (already present in the literature)
are considered here, together with the strategies they use to face the communication problem, and some parallelism methods
for string rewriting are defined. We give a survey of all known results about each variant and we state some relations among
the three variants, thus establishing hierarchies of parallel rewriting P systems. Various open problems related to the subject
are also presented.
Danicla Besozzi: She is assistant professor at the University of Milano. She received her M.S. in Mathematics (2000) from the University
of Como and Ph.D. in Computer Science (2004) from the University of Milano. Her research interests cover topics in Formal
Language Theory, Molecular Computing, Systems Biology. She is member of EATCS (European Association for Theoretical Computer
Science) and EMCC (European Molecular Computing Consortium).
Giancarlo Mauri: He is full professor of Computer Science at the University of Milano-Bicocca. His research interests are mainly in the area
of theoretical computer science, and include: formal languages and automata, computational complexity, computational learning
theory, soft computing techniques, cellular automata, bioinformatics and molecular computing. On these subjects, he published
more than 150 scientific papers in international journals, contributed volumes and conference proceedings.
Claudio Zandron: He received Ph.D. in Computer Science at the University of Milan, Italy, in 2001. Since 2002 he is assistant professor at
the University of Milano-Bicocca, Italy. He is member of the EATCS (European Association for Theoretical Computer Science)
and of EMCC (European Molecular Computing Consortium). His research interests are Molecular Computing (DNA and Membrane Computing)
and Formal Languages. 相似文献
55.
Proteins as biomarkers of oxidative/nitrosative stress in diseases: the contribution of redox proteomics 总被引:8,自引:0,他引:8
Dalle-Donne I Scaloni A Giustarini D Cavarra E Tell G Lungarella G Colombo R Rossi R Milzani A 《Mass spectrometry reviews》2005,24(1):55-99
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) contribute to the pathogenesis and/or progression of several human diseases. Proteins are important molecular signposts of oxidative/nitrosative damage. However, it is generally unresolved whether the presence of oxidatively/nitrosatively modified proteins has a causal role or simply reflects secondary epiphenomena. Only direct identification and characterization of the modified protein(s) in a given pathophysiological condition can decipher the potential roles played by ROS/RNS-induced protein modifications. During the last few years, mass spectrometry (MS)-based technologies have contributed in a significant way to foster a better understanding of disease processes. The study of oxidative/nitrosative modifications, investigated by redox proteomics, is contributing to establish a relationship between pathological hallmarks of disease and protein structural and functional abnormalities. MS-based technologies promise a contribution in a new era of molecular medicine, especially in the discovery of diagnostic biomarkers of oxidative/nitrosative stress, enabling early detection of diseases. Indeed, identification and characterization of oxidatively/nitrosatively modified proteins in human diseases has just begun. 相似文献
56.
Olimpia Daniela Frent Laura Gratiela Vicas Narcis Duteanu Claudia Mona Morgovan Tunde Jurca Annamaria Pallag Mariana Eugenia Muresan Sanda Monica Filip Roxana-Liana Lucaciu Eleonora Marian 《International journal of molecular sciences》2022,23(20)
From the multitude of materials currently available on the market that can be used in the development of microparticles, sodium alginate has become one of the most studied natural anionic polymers that can be included in controlled-release pharmaceutical systems alongside other polymers due to its low cost, low toxicity, biocompatibility, biodegradability and gelatinous die-forming capacity in the presence of Ca2+ ions. In this review, we have shown that through coacervation, the particulate systems for the dispensing of drugs consisting of natural polymers are nontoxic, allowing the repeated administration of medicinal substances and the protection of better the medicinal substances from degradation, which can increase the capture capacity of the drug and extend its release from the pharmaceutical form. 相似文献
57.
Michal Becker-Cohen Ari Zimran Tama Dinur Maayan Tiomkin Claudia Cozma Arndt Rolfs David Arkadir Elena Shulman Orly Manor Ora Paltiel Gilad Yahalom Daniela Berg Shoshana Revel-Vilk 《International journal of molecular sciences》2022,23(20)
Carriers of GBA1 gene variants have a significant risk of developing Parkinson’s disease (PD). A cohort study of GBA carriers between 40–75 years of age was initiated to study the presence of prodromal PD features. Participants underwent non-invasive tests to assess different domains of PD. Ninety-eight unrelated GBA carriers were enrolled (43 males) at a median age (range) of 51 (40–74) years; 71 carried the N370S variant (c.1226A > G) and 25 had a positive family history of PD. The Montreal Cognitive Assessment (MoCA) was the most frequently abnormal (23.7%, 95% CI 15.7–33.4%), followed by the ultrasound hyperechogenicity (22%, 95% CI 14–32%), Unified Parkinson’s Disease Rating Scale part III (UPDRS-III) (17.2%, 95% CI 10.2–26.4%), smell assessment (12.4%, 95% CI 6.6–20.6%) and abnormalities in sleep questionnaires (11%, 95% CI 5.7–19.4%). Significant correlations were found between tests from different domains. To define the risk for PD, we assessed the bottom 10th percentile of each prodromal test, defining this level as “abnormal”. Then we calculated the percentage of “abnormal” tests for each subject; the median (range) was 4.55 (0–43.5%). Twenty-two subjects had more than 15% “abnormal” tests. The limitations of the study included ascertainment bias of individuals with GBA-related PD in relatives, some incomplete data due to technical issues, and a lack of well-characterized normal value ranges in some tests. We plan to enroll additional participants and conduct longitudinal follow-up assessments to build a model for identifying individuals at risk for PD and investigate interventions aiming to delay the onset or perhaps to prevent full-blown PD. 相似文献
58.
Bianca Papotti Maria Pia Adorni Cinzia Marchi Francesca Zimetti Nicoletta Ronda Giovanni Panighel Maria Giovanna Lupo Antonietta Vilella Daniela Giuliani Nicola Ferri Franco Bernini 《International journal of molecular sciences》2022,23(20)
The Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) involvement in Alzheimer’s disease (AD) is poorly investigated. We evaluated the in vitro PCSK9 modulation of astrocyte cholesterol metabolism and neuronal cholesterol supplying, which is fundamental for neuronal functions. Moreover, we investigated PCSK9 neurotoxic effects. In human astrocytoma cells, PCSK9 reduced cholesterol content (−20%; p < 0.05), with a greater effect in presence of beta amyloid peptide (Aβ) (−37%; p < 0.01). PCSK9 increased cholesterol synthesis and reduced the uptake of apoE-HDL-derived cholesterol (−36%; p < 0.0001), as well as the LDL receptor (LDLR) and the apoE receptor 2 (ApoER2) expression (−66% and −31%, respectively; p < 0.01). PCSK9 did not modulate ABCA1- and ABCG1-cholesterol efflux, ABCA1 levels, or membrane cholesterol. Conversely, ABCA1 expression and activity, as well as membrane cholesterol, were reduced by Aβ (p < 0.05). In human neuronal cells, PCSK9 reduced apoE-HDL-derived cholesterol uptake (−41%; p < 0.001) and LDLR/apoER2 expression (p < 0.05). Reduced cholesterol internalization occurred also in PCSK9-overexpressing neurons exposed to an astrocyte-conditioned medium (−39%; p < 0.001). PCSK9 reduced neuronal cholesterol content overall (−29%; p < 0.05) and increased the Aβ-induced neurotoxicity (p < 0.0001). Our data revealed an interfering effect of PCSK9, in cooperation with Aβ, on brain cholesterol metabolism leading to neuronal cholesterol reduction, a potentially deleterious effect. PCSK9 also exerted a neurotoxic effect, and thus represents a potential pharmacological target in AD. 相似文献
59.