1,546 research outputs found
Incremental Predictive Process Monitoring: How to Deal with the Variability of Real Environments
A characteristic of existing predictive process monitoring techniques is to
first construct a predictive model based on past process executions, and then
use it to predict the future of new ongoing cases, without the possibility of
updating it with new cases when they complete their execution. This can make
predictive process monitoring too rigid to deal with the variability of
processes working in real environments that continuously evolve and/or exhibit
new variant behaviors over time. As a solution to this problem, we propose the
use of algorithms that allow the incremental construction of the predictive
model. These incremental learning algorithms update the model whenever new
cases become available so that the predictive model evolves over time to fit
the current circumstances. The algorithms have been implemented using different
case encoding strategies and evaluated on a number of real and synthetic
datasets. The results provide a first evidence of the potential of incremental
learning strategies for predicting process monitoring in real environments, and
of the impact of different case encoding strategies in this setting
Severe chest allodynia as an unusual first presentation of hydatid disease. A case report
Background: Cystic echinococcosis (CE) is a worldwide zoonosis and the liver is the most commonly affected organ. Clinical manifestations range from completely asymptomatic cysts to a potential lethal cyst rupture and anaphylaxis. Case presentation: Severe chest allodynia was an unusual clinical presentation of hepatic cyst rupture in the retroperitoneal space, without any other specific symptoms. CE diagnosis was confirmed by computed tomography scan and magnetic resonance. The patient underwent hepatectomy with complete resolution of the neuropathic pain. Conclusions: Retroperitoneal hydatid cyst rupture is a rare event and its clinical manifestation may mimic other chest neuropathies
The Glutaminase-dependent system confers extreme acid resistance to new species and atypical strains of Brucella
Neutralophilic bacteria have developed specific mechanisms to cope with the acid stress encountered in environments such as soil, fermented foods, and host compartments. In Escherichia coli, the glutamate decarboxylase (Gad)-dependent system is extremely efficient: it requires the concerted action of glutamate decarboxylase (GadA/GadB) and of the glutamate (Glu)/γ-aminobutyrate antiporter, GadC. Notably, this system is operative also in new strains/species of Brucella, among which Brucella microti, but not in the "classical" species, with the exception of marine mammals strains. Recently, the glutaminase-dependent system (named AR2_Q), relying on the deamination of glutamine (Gln) into Glu and on GadC activity, was described in E. coli. In Brucella genomes, a putative glutaminase (glsA)-coding gene is located downstream of the gadBC genes. We found that in B. microti these genes are expressed as a polycistronic transcript. Moreover, using a panel of Brucella genus-representative strains, we show that the AR2_Q system protects from extreme acid stress (pH =2.5), in the sole presence of Gln, only the Brucella species/strains predicted to have functional glsA and gadC. Indeed, mutagenesis approaches confirmed the involvement of glsA and gadC of B. microti in AR2_Q and that the acid-sensitive phenotype of B. abortus can be ascribed to a Ser248Leu substitution in GlsA, leading to loss of glutaminase activity. Furthermore, we found that the gene BMI_II339, of unknown function and downstream of the gadBC-glsA operon, positively affects Gad- and GlsA-dependent AR. Thus, we identified novel determinants that allow newly discovered and marine mammals Brucella strains to be better adapted to face hostile acidic environments. As for significance, this work may contribute to the understanding of the host preferences of Brucella species and opens the way to alternative diagnostic targets in epidemiological surveillance of brucellosis
Ulteriori evidenze di attività antimicrobiche in invertebrati marini
The antimicrobial molecules are an abundant group of molecules that are amply distributed in nature, from plants and insects to vertebrate animals, including humans. They are an essential component of the innate immune system for host defence against pathogenic agents of different types. They are often the products of individual genes and circulating cells. In this thesis, based on a bioinformatic analysis, we identified three peptides, members to the family of cathelicidins and to the class of peptides rich in proline (PR-AMPs), that may be generally be considered as the first effectors of the interior defense, acting as natural antibiotics (Scocchi et al., 2011; Reddy et al., 2004). We investigate, also, about the possibility of use four extracts from marine invertebrates as possible natural antibiotics. Their small size makes them able to spread rapidly at sites of infection, they are also cheap to synthesize, relatively resistant to denaturation and are less likely to induce resistance. The objective of this doctoral thesis was to deepen the knowledge on the ability of peptides and molecules with antimicrobial activity, initially identified or isolated from different marine invertebrates. The studied peptides show a broad spectrum of activity against a variety of microorganisms such as Gram-positive bacteria, Gram-negative bacteria and fungi. Furthermore, it was interesting to determine the cytotoxic activity of peptides and antimicrobial molecules versus the murine monocytic cell line J774-A1 coming from sarcoma of Balb / c mice. The surprising results, especially on the analysis of peptides, make them interesting to understand the mechanisms of innate immunity evolution and trace an original point of view on a new frontier for the control of microbial infections that could, therefore, be a good alternative for their use in biotechnology and in the pharmaceutical field (Schnapp et al., 1996)
Beyond islet trasplantation in diabetes cell terapy:from embryonic stem cells to transdifferentation of adult cells
Exogenous insulin is, at the moment, the therapy of choice of diabetes, but does not allow
tight regulation of glucose leading to long-term complications. Recently, pancreatic islet
transplantation to reconstitute insulin-producing cells, has emerged as an alternative
promising therapeutic approach. Unfortunately, the number of donor islets is too low
compared with the high number of patients needing a transplantation leading to a search
for renewable sources of high-quality -cells. This review, summarizes more recent
promising approaches to the generation of new -cells from embryonic stem cells for
transdifferentiation of adult cells, particularly a critical examination of the seminal work by
Lumelsky et al
Long-term comparative analysis of no evidence of disease activity (NEDA-3) status between multiple sclerosis patients treated with natalizumab and fingolimod for up to 4 years
Comparative effectiveness of natalizumab and fingolimod over a follow-up longer than 2 years has been not addressed yet
TeV neutrinos and hard X-rays from relativistic reconnection in the corona of NGC 1068
The recent discovery of astrophysical neutrinos from the Seyfert galaxy NGC
1068 suggests the presence of non-thermal protons within a compact "coronal"
region close to the central black hole. The acceleration mechanism of these
non-thermal protons remains elusive. We show that a large-scale magnetic
reconnection layer, of the order of a few gravitational radii, may provide such
a mechanism. In such a scenario, rough energy equipartition between magnetic
fields, X-ray photons, and non-thermal protons is established in the
reconnection region. Motivated by recent three-dimensional particle-in-cell
simulations of relativistic reconnection, we assume that the spectrum of
accelerated protons is a broken power law, with the break energy being
constrained by energy conservation (i.e., the energy density of accelerated
protons is at most comparable to the magnetic energy density). The proton
spectrum is below the break, and above the break, with IceCube neutrino observations suggesting . Protons above the break lose most of their energy within the
reconnection layer via photohadronic collisions with the coronal X-rays,
producing a neutrino signal in good agreement with the recent observations.
Gamma-rays injected in photohadronic collisions are cascaded to lower energies,
sustaining the population of electron-positron pairs that makes the corona
moderately Compton thick.Comment: 8 pages, 3 figures, with Appendice
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