146 research outputs found
Black Lenses in Kaluza-Klein Matter
We present the first examples of formally asymptotically flat black hole
solutions with horizons of general lens space topology . These
5-dimensional static/stationary spacetimes are regular on and outside the event
horizon for any choice of relatively prime integers , in particular
conical singularities are absent. They are supported by Kaluza-Klein matter
fields arising from higher dimensional vacuum solutions through reduction on
tori. The technique is sufficiently robust that it leads to the explicit
construction of regular solutions, in any dimension, realising the full range
of possible topologies for the horizon as well as the domain of outer
communication, that are allowable with multi-axisymmetry. Lastly, as a by
product, we obtain new examples of regular gravitational instantons in higher
dimensions.Comment: 6 pages; Phys. Rev. Lett., to appear; A Quanta Magazine article based
on the results of this paper may be found here:
https://www.quantamagazine.org/mathematicians-find-an-infinity-of-possible-black-hole-shapes-20230124
Seismic Characterisation of Soils with SPT: Comparison of Calculated vs Values and Measured vs Values
Italian seismic regulatory guidance (O.P.C.M. n. 3274 of 20 March 2003, O.P.C.M. n. 3519 of 28 April 2006, implemented within the “Norme Tecniche per le Costruzioni” – D.M. of 14 January 2008) which conforms to European guidance (Eurocode 8), advises a seismic classification of foundation soils through the Vs30 value or alternatively the Nspt value. Several correlations between the Nspt parameter and the Vs parameter are known in literature (Otha & Goto, 1978; Imai & Tonouchi, 1982; Ohsaki & Iwasaki, 1977; Seed, 1983). Each of these correlations can only be applied in certain geological-technical contexts. The validity of these correlations should be discussed considering that geophysical investigations are undertaken under elastic deformation conditions where induced stress causes reversible deformations. Instead, SPT investigations cause rupture of the investigated material and they cannot be conducted within all types of deposits. This note presents the results obtained by comparison of Vs values from SPT investigations and the Vs values from down-hole investigations measured on the same vertical and at the same depth. The study is based on a great quantity of data (153 pairs of Nspt-Vs values) which were acquired from different geological-technical contexts. The data were acquired within the VEL project of the Tuscany Region (Central Italy) aimed at assessing local effects in areas where different seismic hazards exist. Limits and applicability of these empirical correlations are discussed
Low-frequency vibrational spectrum of mean-field disordered systems
We study a recently introduced and exactly solvable mean-field model for the density of vibrational states D(ω) of a structurally disordered system. The model is formulated as a collection of disordered anharmonic oscillators, with random stiffness κ drawn from a distribution p(κ), subjected to a constant field h and interacting bilinearly with a coupling of strength J. We investigate the vibrational properties of its ground state at zero temperature. When p(κ) is gapped, the emergent D(ω) is also gapped, for small J. Upon increasing J, the gap vanishes on a critical line in the (h, J) phase diagram, whereupon replica symmetry is broken. At small h, the form of this pseudogap is quadratic, D(ω) ~ ω2, and its modes are delocalized, as expected from previously investigated mean-field spin glass models. However, we determine that for large enough h, a quartic pseudogap D(ω) ~ ω4, populated by localized modes, emerges, the two regimes being separated by a special point on the critical line. We thus uncover that mean-field disordered systems can generically display both a quadratic-delocalized and a quartic-localized spectrum at the glass transition.</p
Pathology Reporting in Neuroendocrine Neoplasms of the Digestive System: Everything You Always Wanted to Know but Were Too Afraid to Ask
During the 5th NIKE (Neuroendocrine tumors Innovation in Knowledge and Education) meeting, held in Naples, Italy, in May 2019, discussions centered on the understanding of pathology reports of gastroenetropancreactic neuroendocrine neoplasms. In particular, the main problem concerned the difficulty that clinicians experience in extrapolating relevant information from neuroendocrine tumor pathology reports. During the meeting, participants were asked to identify and rate issues which they have encountered, for which the input of an expert pathologist would have been appreciated. This article is a collection of the most rated questions and relative answers, focusing on three main topics: 1) morphology and classification; 2) Ki67 and grading; 3) immunohistochemistry. Patient management should be based on multidisciplinary decisions, taking into account clinical and pathology-related features with clear comprehension between all health care professionals. Indeed, pathologists require clinical details and laboratory findings when relevant, while clinicians require concise and standardized reports. In keeping with this last statement, the minimum requirements in pathology datasets are provided in this paper and should be a baseline for all neuroendocrine tumor professionals
Green line hospital-territory study: A single-blind randomized clinical trial for evaluation of technological challenges of continuous wireless monitoring in internal medicine, preliminary results
Background: Wireless vital parameter continuous monitoring (WVPCM) after discharge is compared to regular monitoring to provide data on the clinical-economic impact of complex patients (CPs) discharged from Internal Medicine Units of Ospedale dei Castelli, Lazio. Primary outcome: Major complications (MC) reduction. Secondary outcomes: Patients who reached discharge criteria within the 7th day from admission; difference in MC incidence at the conclusion of the standard telemonitoring/clinical monitoring phase, 5 and 30 days after discharge; and conditions predisposing to MC occurrence. Methods: Open label randomized controlled trial with wearable wireless system that creates alerts on portable devices. Continuous glycemic monitoring is performed for patients with diabetes mellitus. Results: There were 110 patients enrolled (mean age: 76.2 years). Comorbidity: Cumulative Illness Rating Scale CIRS-CI (comorbidities index): 3.93, CIRS SI (severity index): 1.93. About 19% scored a BRASS (Blaylock Risk Assessment Screening Score) ≥20 indicating need for discharge planning requiring step-down care. Globally, 48% of patients in the control group had major complications (27 out of 56 patients), in contrast to 22% in the intervention group (12 out of 54 patients). Conclusions: Since WVPCM detects early complications during the post-discharge CPs monitoring, it increases safety and reduces inappropriate access to the Emergency Room, preventing avoidable re-hospitalizations
Task 1 - Deliverable 7: Strong motion data base
Database dati accelerometriciProgetto DPC-INGV S6 “Data base dei dati accelerometrici Italiani relativi al periodo 1972-2004"Published5.2. TTC - Banche dati di sismologia strumentaleope
Plasma and PBMC miRNA profile in sexually HIV-1 exposed seronegative individuals
Background: MicroRNAs (miRNAs) are small 20- to 24-nt non-coding RNAs involved in the post-transcriptional regulation of gene expression which play important defensive roles in several viral infections. Global expression profiles of cellular miRNAs have identified alterations of specific miRNAs post-HIV-1 infection both in vitro and in different patient cohorts suggesting potential roles for miRNA in pathogenesis and disease progression. We therefore decided to verify if natural resistance to HIV-1 infection observed in seronegative individuals repeatedly exposed to HIV-1 (HESN) through unprotected sexual intercourse could be secondary to a different expression of their miRNA profile. Methods: Expression levels of 25 miRNAs selected according to their proven anti-HIV-1 properties were analyzed in plasma, basal PBMC and in in vitro HIV-1 infected macrophages isolated from 30 HESN, 30 HIV seropositive subjects (HIV + ) and 30 healthy controls (HC).Results: In plasma the expression of mir-155, mir-382, mir-28
and mir-198 was significantly augmented in both HIV + and HESN compared to HC probably as a consequence of viral exposure.
Conversely the expression of mir-223 and mir-150 in plasma was significantly increased only in HESN and this result was also confirmed in basal PBMC suggesting a protective effect for these miRNAs in resistance to HIV-1 infection. Furthermore, the expression of mir-150 was significantly increased in HESN macrophages following HIV-1 infection. Conclusions: mir-223 and mir-150 can target the 3\ua2UTR of HIV-1 transcripts, and they have already been identified as anti-HIV-1 miRNAs. The higher expression of these miRNA in HESN samples could therefore represent a key protection mechanism against HIV infection
Partial oxidation of toluene by O2 over mesoporous Cr/AlPO
The prepn. of mesoporous Cr/AlPO was carried out under hydrothermal conditions. The catalyst was characterized by low angle XRD, N-adsorption, diffuse reflectance UV-visible spectroscopy, ESR and thermal anal. The catalytic activity was tested for vapor phase partial oxidn. of toluene with O to benzaldehyde. The catalyst functions both as an acid and redox catalyst. [on SciFinder (R)
Catalytic oxidation of toluene with molecular oxygen over Cr-substituted mesoporous materials
Syntheses of thermally stable chromium-incorporating hexagonal mesoporous aluminophosphate and cubic Cr-MCM-48 were reported. Characterization of the catalysts was made using low angle XRD, N2 adsorption, UV-VISDRS, thermal anal., ICP-AES and ESR. Mesoporous Cr-AlPO4 and Cr-MCM-48 catalysts have been found to be active for the vapor phase oxidn. of toluene with mol. oxygen. Mesoporous Cr-AlPO4 is found to exhibit both acidic and redox properties and hence oxidn. as well as dealkylation reactions are taking place in a concerted manner, whereas, the cubic silicate analog acts as a pure redox catalyst. [on SciFinder (R)
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