192 research outputs found
Imaging of Scarce Archaeological Remains Using Microwave Tomographic Depictions of Ground Penetrating Radar Data
The Romano-British site of Barcombe in East Sussex, England, has suffered heavy postdepositional attrition through reuse of the building materials for the effects of ploughing. A detailed GPR survey of the site was carried out in 2001, with results, achieved by usual radar data processing, published in 2002.
The current paper reexamines the GPR data using microwave tomography approach, based on a linear inverse scattering model, and a 3D visualization that permits to improve the definition of the villa plan and reexamine the possibility of detecting earlier prehistoric remains
Ground Penetrating Radar in Dam Monitoring: The Test Case of Acerenza (Southern Italy)
Nowadays, dam safety management is gaining great importance since it affects in a crucial way the monitoring and improvement of risky reservoirs, but this topic is very challenging since the dam safety requires long-term and time-continuous monitoring. In this framework, the exploitation of conventional geotechnical investigation methods often requires invasive actions in the inner of the structure to be investigated (destructiveness) and only provides punctual information for small volumes. On the contrary, the application of noninvasive sensing techniques makes it possible to investigate higher volumes without affecting the structure. In this paper we describe the application of GPR for the monitoring and diagnostics of one of the largest dams in the Basilicata region (Southern Italy). The investigation aims at detecting and localizing underground sandstone banks that are potential ways of flow of water below the dam. The manageability and the noninvasiveness of GPR have resulted in particularly suitable for this kind of application because the versatility of this geophysical method allows to investigate large areas with a good spatial resolution giving the possibility to detect the presence of inhomogeneities in the subsoil below the dam
Integrated geophysical survey to recognize ancient Picentiaâs buried walls, in the Archaeological Park of Pontecagnano â Faiano (Southern Italy)
There is no information on previous geophysical prospections carried out in the Archaeological Park of Pontecagnano-
Faiano, in order to reconstruct the ancient settlement of Picentia, an Etrusco-Campanian and Roman
settlement near Salerno (Southern Italy). Therefore, an integrated geophysical survey based on magnetic, geoelectric
and ground-penetrating radar (GPR) prospections was executed in the Park. The methods provided a
basic map of buried ancient structures at depth from 0.1-0.2 to about 1.5 meters. Magnetic data were processed
analyzing the analytical signal of the vertical derivative of the measured gradient and this substantially reduced
a strong fence effect. The results of the geophysical prospections showed archaeological structures located close
to those discovered in the excavated areas. The shape of the anomalies are usually elongated with well-defined
geometrical characteristics. Many anomalies are arranged along orthogonal directions and they are very coherent
with the excavated structures, namely the quarters structures of the ancient Picentia
Variational and Potential Formulation for Stochastic Partial Differential Equations
There is recent interest in finding a potential formulation for Stochastic
Partial Differential Equations (SPDEs). The rationale behind this idea lies in
obtaining all the dynamical information of the system under study from one
single expression. In this Letter we formally provide a general Lagrangian
formalism for SPDEs using the Hojman et al. method. We show that it is possible
to write the corresponding effective potential starting from an s-equivalent
Lagrangean, and that this potential is able to reproduce all the dynamics of
the system, once a special differential operator has been applied. This
procedure can be used to study the complete time evolution and spatial
inhomogeneities of the system under consideration, and is also suitable for the
statistical mechanics description of the problem. Keywords: stochastic partial
differential equations, variational formulation, effective potential. PACS:
45.20.Jj; 02.50.-r; 02.50.Ey.Comment: Letter, 4 pages, no figures; v2: references added, minor change
The Use of GPR and Microwave Tomography for the Assessment of the Internal Structure of Hollow Trees
Peer reviewedPostprin
A novel KCNQ3 mutation in familial epilepsy with focal seizures and intellectual disability
Mutations in the KCNQ2 gene encoding for voltage-gated potassium channel subunits have been
found in patients affected with early-onset epilepsies with wide phenotypic expression, ranging
from Benign Familial Neonatal Seizures (BFNS) to epileptic encephalopathy with cognitive
impairment, drug resistance, and characteristic EEG and neuroradiological features. By contrast,
only few KCNQ3 mutations have been rarely described, mostly in patients with typical BFNS. We
report clinical, genetic, and functional data from a family in which early-onset epilepsy and
neurocognitive deficits segregated with a novel mutations in KCNQ3 (c.989G>T; p.R330L).
Electrophysiological studies in mammalian cells revealed that incorporation of KCNQ3 R330L
mutant subunits impaired channel function, suggesting a pathogenetic role for such mutation. The
degree of functional impairment of channels incorporating KCNQ3 R330L subunits was larger than
that of channels carrying another KCNQ3 mutation affecting the same codon but leading to a
different amino acid substitution (p.R330C), previously identified in two families with typical
BFNS. These data suggest that mutations in KCNQ3, similarly to KCNQ2, can be found in patients
with more severe phenotypes including intellectual disability, and that the degree of the functional
impairment caused by mutations at position 330 in KCNQ3 may contribute to clinical disease
severity
Activation of Kv7 potassium channels inhibits intracellular Ca2+ increases triggered by TRPV1-mediated pain-inducing stimuli in F11 immortalized sensory neurons
Kv7.2-Kv7.5 channels mediate the M-current (IKM), a K+-selective current regulating neuronal excitability and representing an attractive target for pharmacological therapy against hyperexcitability diseases such as pain. Kv7 channels interact functionally with transient receptor potential vanilloid 1 (TRPV1) channels activated by endogenous and/or exogenous pain-inducing substances, such as bradykinin (BK) or capsaicin (CAP), respectively; however, whether Kv7 channels of specific molecular composition provide a dominant contribution in BK- or CAP-evoked responses is yet unknown. To this aim, Kv7 transcripts expression and function were assessed in F11 immortalized sensorial neurons, a cellular model widely used to assess nociceptive molecular mechanisms. In these cells, the effects of the pan-Kv7 activator retigabine were investigated, as well as the effects of ICA-27243 and (S)-1, two Kv7 activators acting preferentially on Kv7.2/Kv7.3 and Kv7.4/Kv7.5 channels, respectively, on BK- and CAP-induced changes in intracellular Ca2+ concentrations ([Ca2+]i). The results obtained revealed the expression of transcripts of all Kv7 genes, leading to an IKM-like current. Moreover, all tested Kv7 openers inhibited BK- and CAP-induced responses by a similar extent (~60%); at least for BK-induced Ca2+ responses, the potency of retigabine (IC50~1 ”M) was higher than that of ICA-27243 (IC50~5 ”M) and (S)-1 (IC50~7 ”M). Altogether, these results suggest that IKM activation effectively counteracts the cellular processes triggered by TRPV1-mediated pain-inducing stimuli, and highlight a possible critical contribution of Kv7.4 subunits
Chapter Electromagnetic Sensing Techniques for Non-Destructive Diagnosis of Civil Engineering Structures
Environmental policy & protocol
Functional analysis of novel KCNQ2 and KCNQ3 gene variants found in a large pedigree with benign familial neonatal convulsions (BFNC)
Benign familial neonatal convulsion (BFNC) is a rare autosomal dominant disorder caused by mutations in KCNQ2 and KCNQ3, two genes encoding for potassium channel subunits. A large family with nine members affected by BFNC is described in the present study. All affected members of this family carry a novel deletion/insertion mutation in the KCNQ2 gene (c.761_770del10insA), which determines a premature truncation of the protein. In addition, in the family of the proposita's father, a novel sequence variant (c.2687A>G) in KCNQ3 leading to the p.N821S amino acid change was detected. When heterologously expressed in Chinese hamster ovary cells, KCNQ2 subunits carrying the mutation failed to form functional potassium channels in homomeric configuration and did not affect channels formed by KCNQ2 and/or KCNQ3 subunits. On the other hand, homomeric and heteromeric potassium channels formed by KCNQ3 subunits carrying the p.N821S variant were indistinguishable from those formed by wild-type KCNQ3 subunits. Finally, the current density of the cells mimicking the double heterozygotic condition for both KCNQ2 and KCNQ3 alleles of the proband was decreased by approximately 25% when compared to cells expressing only wild-type alleles. Collectively, these results suggest that, in the family investigated, the KCNQ2 mutation is responsible for the BFNC phenotype, possibly because of haplo-insufficiency, whereas the KCNQ3 variant is functionally silent, a result compatible with its lack of segregation with the BFNC phenotyp
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