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211.
On the GeV Emission of the Type I BdHN GRB 130427A
Remo Ruffini, Rahim Moradi, Jorge Armando Rueda, Carlo Luciano Bianco, Christian Cherubini, Simonetta Filippi, Yen-Chen Chen, Mile Karlica, Narek Sahakyan, Yu Wang, She Sheng Xue, Laura Beccera, 2019, izvirni znanstveni članek

Opis: We propose that the inner engine of a type I binary-driven hypernova (BdHN) is composed of Kerr black hole (BH) in a non-stationary state, embedded in a uniform magnetic field B_0 aligned with the BH rotation axis and surrounded by an ionized plasma of extremely low density of 10^−14 g cm−3. Using GRB 130427A as a prototype, we show that this inner engine acts in a sequence of elementary impulses. Electrons accelerate to ultrarelativistic energy near the BH horizon, propagating along the polar axis, θ = 0, where they can reach energies of ~10^18 eV, partially contributing to ultrahigh-energy cosmic rays. When propagating with $\theta \ne 0$ through the magnetic field B_0, they produce GeV and TeV radiation through synchroton emission. The mass of BH, M = 2.31M ⊙, its spin, α = 0.47, and the value of magnetic field B_0 = 3.48 × 10^10 G, are determined self consistently to fulfill the energetic and the transparency requirement. The repetition time of each elementary impulse of energy ${ \mathcal E }\sim {10}^{37}$ erg is ~10^−14 s at the beginning of the process, then slowly increases with time evolution. In principle, this "inner engine" can operate in a gamma-ray burst (GRB) for thousands of years. By scaling the BH mass and the magnetic field, the same inner engine can describe active galactic nuclei.
Ključne besede: black hole physics, binaries, gamma-ray burst, neutron stars, supernovae, Astrophysics - High Energy Astrophysical Phenomena
Objavljeno v RUNG: 20.07.2020; Ogledov: 2869; Prenosov: 0
Gradivo ima več datotek! Več...

212.
Magnetic Fields and Afterglows of BdHNe: Inferences from GRB 130427A, GRB 160509A, GRB 160625B, GRB 180728A, and GRB 190114C
Jorge Armando Rueda, Remo Ruffini, Mile Karlica, Rahim Moradi, Yu Wang, 2020, izvirni znanstveni članek

Opis: GRB 190114C is the first binary-driven hypernova (BdHN) fully observed from initial supernova (SN) appearance to the final emergence of the optical SN signal. It offers an unprecedented testing ground for the BdHN theory, which is here determined and further extended to additional gamma-ray bursts (GRBs). BdHNe comprise two subclasses of long GRBs, with progenitors a binary system composed of a carbon–oxygen star (COcore) and a neutron star (NS) companion. The COcore explodes as an SN, leaving at its center a newborn NS (νNS). The SN ejecta hypercritically accretes on both the νNS and the NS companion. BdHNe I are very tight binaries, where the accretion leads the companion NS to gravitationally collapse into a black hole (BH). In BdHN II, the accretion rate onto the NS is lower, so there is no BH formation. We observe the same afterglow structure for GRB 190114C and other selected examples of BdHNe I (GRB 130427A, GRB 160509A, GRB 160625B) and for BdHN II (GRB 180728A). In all cases, the afterglows are explained via the synchrotron emission powered by the νNS, and their magnetic field structures and their spin are determined. For BdHNe I, we discuss the properties of the magnetic field embedding the newborn BH, which was inherited from the collapsed NS and amplified during the gravitational collapse process, and surrounded by the SN ejecta.
Ključne besede: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, General Relativity and Quantum Cosmology
Objavljeno v RUNG: 20.07.2020; Ogledov: 2631; Prenosov: 0
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213.
Coupling of autoionizing states by a chirped laser pulse
Matjaž Žitnik, Andrej Mihelič, Klemen Bučar, Mateja Hrast, Žiga Barba, Špela Krušič, Primož Rebernik Ribič, Jurij Urbančič, Barbara Ressel, Matija Stupar, David Gauthier, Giovanni De Ninno, 2020, objavljeni povzetek znanstvenega prispevka na konferenci

Opis: We have observed the autoionization of the laser-coupled 2s2p 1Po and 2p2 1Se resonances in helium. The ions were collected while varying the frequency and delay of the extreme-ultraviolet (EUV) excitation pulse with respect to the linearly chirped visible (VIS) laser pulse. From the measured frequency-delay map the Autler- Townes splitting, the EUV-VIS cross-correlation and the linear chirp parameter were extracted.
Ključne besede: High Harmonic Generation
Objavljeno v RUNG: 29.06.2020; Ogledov: 3149; Prenosov: 0
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214.
215.
Implementation of high performance liquid chromatography coupled to thermal lens spectrometry (HPLC‑TLS) for quantification of pyranoanthocyanins during fermentation of Pinot Noir grapes
Jelena Topič Božič, Lorena Butinar, Natka Ćurko, Karin Kovačević Ganić, Branka Mozetič Vodopivec, Dorota Korte, Mladen Franko, 2020, izvirni znanstveni članek

Opis: In this work high performance liquid chromatography coupled to thermal lens spectrometry (HPLC-TLS) was applied for monitoring of vinylphenolic pyranoanthocyanins formation during the fermentation of Pinot Noir wines. Vinylphenolic pyranoanthocyanins are wine pigments, present in low concentrations, but very important for wine colour stability. Fermentation process was conducted with four different yeast strains, used as starters, either in sequential fermentation of non-Saccharomyces with S. cerevisiae yeast or as single fermentation with S. cerevisiae yeasts in order to test the applicability of developed method for monitoring of selected compounds in real wine fermentation experiments. The developed HPLC-TLS method showed higher sensitivity compared to HPLC coupled to diode array detection (DAD) technique for particular wine colour compounds. Obtained limits of detection (LODs), were 6- and 22-times lower in comparison to HPLC–DAD in gradient and isocratic elution mode, respectively, whereas limits of quantification (LOQs) 5 and 18-times lower. Lower LODs enabled earlier observation of vinylphenolic pyranoanthocyanins formation during fermentation (already at day 7) in the case of HPLC-TLS method in gradient mode, while by using HPLC–DAD in gradient elution mode the formation of vinylphenolic pyranoanthocyanins was noticed only after 12 days of fermentation.
Ključne besede: Thermal lens spectrometry (TLS), High performance liquid chromatography (HPLC), Pyranoanthocyanins, Wine, Yeasts
Objavljeno v RUNG: 18.06.2020; Ogledov: 3305; Prenosov: 0
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216.
DEVELOPMENT OF A NOVEL PCR-BASED ASSAY FOR HIGH-RISK HUMAN PAPILLOMAVIRUS DETECTION AND GENOTYPING IN SELF COLLECTED CERVICOVAGINAL SAMPLES: A NEW POSSIBILITY FOR THE CERVICAL CANCER SCREENING
Alice Avian, 2020, doktorska disertacija

Opis: Human Papillomavirus (HPV) infection is the causative agent for the invasive cervical cancer and its precancerous lesions, furthermore, there are growing evidences of HPV being a relevant factor in other anogenital cancers as well as head and neck cancers. Most sexually active women become infected with HPV at least once in their lifetime, but less than 10% of women becomes persistently infected, and it is precisely the persistent infection that contributes to the development of cervical cancer. The preventive effect of cervical cancer screening largely depends in the high women participation and coverage; indeed, a large number of cervical cancers diagnoses normally arise among under-screened and unscreened women. Increase in the screening coverage is essential to improve the effectiveness of cervical screening programmes. The main purpose of this PhD project was to solve some of the most relevant problems in the cervical cancer screening programmes, as the increase of cost-effectiveness and the amelioration of the screening coverage. My work was focused on the development and validation of the first Ulisse BioMed S.p.A. product, the HPV Selfy™ test, an innovative PCR-based kit for the direct detection and genotyping of 12 high-risk HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59) and 2 possible/probable high-risk (66 and 68), specifically optimized for the analysis of self-collected vaginal specimens. The core of this innovative test is based on high-resolution melting (HRM) analysis, a recently developed technique for fast, high-throughput post-PCR analysis of variance in nucleic acid sequences, that characterizes the amplicons by studying thermal denaturation of double-stranded DNA. Based on this approach and through the design of different HPV type-specific primer pairs and the development of a specific master mix, unique melting peaks in a single fluorescence channel were obtained, allowing the multiple detection and genotyping of 14 HPV types in a single PCR well. Three different clinical studies have been carried out to validate the assay on the vaginal self-collected samples with truly amazing results regarding the assay’s performance, but also for self-sampling acceptability by women. Moreover, data collected in these studies suggest a future possible use of this test for the hard-to-reach women, as an alternative of the conventional clinician-collected sample, in order to increase the cervical cancer screening coverage.
Ključne besede: Human Papillomavirus, HPV test, cervical cancer screening, prevention, diagnostic test, High resolution melting, HRM, genotyping, PCR, Self-sampling, clinical validation.
Objavljeno v RUNG: 17.06.2020; Ogledov: 3511; Prenosov: 106
.pdf Celotno besedilo (37,88 MB)

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