The detection of gravitational waves from core-collapse supernova (CCSN) explosions is a challenging task, yet to be achieved, in which it is key the connection between multiple messengers, including ...neutrinos and electromagnetic signals. In this work, we present a method for detecting these kind of signals based on machine learning techniques. We tested its robustness by injecting signals in the real noise data taken by the Advanced LIGO-Virgo network during the second observing run, O2. We trained a newly developed Mini-Inception Resnet neural network using time-frequency images corresponding to injections of simulated phenomenological signals, which mimic the waveforms obtained in 3D numerical simulations of CCSNe. With this algorithm we were able to identify signals from both our phenomenological template bank and from actual numerical 3D simulations of CCSNe. We computed the detection efficiency versus the source distance, obtaining that, for signal to noise ratio higher than 15, the detection efficiency is 70% at a false alarm rate lower than 5%. We notice also that, in the case of the O2 run, it would have been possible to detect signals emitted at 1 kpc of distance, while lowering down the efficiency to 60%, the event distance reaches values up to 14 kpc.
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While gravitational waves have been detected from mergers of binary black holes and binary neutron stars, signals from core collapse supernovae, the most energetic explosions in the modern Universe, ...have not been detected yet. Here we present a new method to analyse the data of the LIGO, Virgo, and KAGRA network to enhance the detection efficiency of this category of signals. The method takes advantage of a peculiarity of the gravitational wave signal emitted in the core collapse supernova and it is based on a classification procedure of the time-frequency images of the network data performed by a convolutional neural network trained to perform the task to recognize the signal. We validate the method using phenomenological waveforms injected in Gaussian noise whose spectral properties are those of the LIGO and Virgo advanced detectors and we conclude that this method can identify the signal better than the present algorithm devoted to select gravitational wave transient signal.
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One of the main objectives of the ANTARES telescope is the search for point-like neutrino sources. Both the pointing accuracy and the angular resolution of the detector are important in this context ...and a reliable way to evaluate this performance is needed. In order to measure the pointing accuracy of the detector, one possibility is to study the shadow of the Moon, i.e. the deficit of the atmospheric muon flux from the direction of the Moon induced by the absorption of cosmic rays. Analysing the data taken between 2007 and 2016, the Moon shadow is observed with
3.5
σ
statistical significance. The detector angular resolution for downward-going muons is
0
.
73
∘
±
0
.
14
∘
.
The resulting pointing performance is consistent with the expectations. An independent check of the telescope pointing accuracy is realised with the data collected by a shower array detector onboard of a ship temporarily moving around the ANTARES location.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
BACKGROUND AND AIMS
The complex system of human adult renal stem/progenitor cells (ARPCs) and their crucial role in the renewal of epithelial renal cells and regenerative processes in the ...adult kidneys have been recently discovered. In the human kidney, CD133+/CD24+ ARPCs are present within different segments of the nephron as a population with epithelial expansion, self-renewal and differentiation capabilities. Understanding the factors that regulate the ARPCs behaviour is fundamental to completely take advantage of their potential and to develop treatments for renal injury.
Recent studies showed that long no-coding RNA (lncRNAs) are essential to establish developmental patterning and maintain the stem cell pluripotency network, further underscoring their important role in stem cell biology/technology and cellular reprogramming. lncRNAs can be dysregulated in different types of diseases and can also modulate the cellular senescence processes.
For the first time, we studied their function in ARPCs showing that they express high levels of a particular lncRNA, HOTAIR, influencing cell senescence.
METHOD
Whole-genome lncRNA expression was performed by Agilent microarray. lncRNA expression was validated by real-time PCR. CRISPR/Cas9 system has been used to knock-down HOTAIR lncRNA. SA-β-Gal experiments were used to evaluate cellular senescence in normal ARPCs and ARPCs knock-out for HOTAIR. By ELISA, it was evaluated the expression of secreted anti-ageing protein Klotho. Fluorescence-activated cell sorting (FACS) was applied to measure CD133 and protein p15 expression in normal and transfected cells. Chromatin immunoprecipitation assay (ChIP) was used to evaluate H3K27me3 in the promoter of p15.
RESULTS
We studied the lncRNA profile of renal proximal tubular cells (RPTEC) and tubular ARPCs. We found 611 lncRNAs specifically expressed in ARPCs compared with RPTECs (Fold Change > 2; FDR < 0.05). Among the most significantly modulated lncRNAs, we demonstrated that the lncRNA HOX Transcript Antisense RNA (HOTAIR) is highly expressed in ARPCs (Fold change = 15; P < 0.001). To study the functions related to the ARPCs properties, knock-out cell lines for HOTAIR were created by the CRISPR/Cas9 technique. The silenced lines for HOTAIR immediately assumed a senescent phenotype confirmed by the beta-galactosidase assay and decreased proliferation (proliferation rate of ˂60%, P < 0.001). Moreover, we found that the constitutional, functional and inverse-senescence marker CD133+ was downregulated in knock-out cells (Fold change = 15; P < 0.01). We then studied the secreted levels of the anti-ageing protein α-Klotho which is essential to the maintenance of normal renal function and has potential clinical applications in the diagnosis of acute renal failure (AKI) and chronic kidney disease (CKD).
We discovered that ARPCs produce α-Klotho at much higher levels compared to RPTEC, at a mean concentration of 200 pg/mL versus 33 pg/mL (Fold increase = 6.6; P < 0.001). Interestingly, following the HOTAIR knock-out, the levels of α-Klotho secreted by the ARPCs dropped sharply, with a 4-fold decrease (P < .001). In addition, we found that HOTAIR was responsible for the ARPC self-renewal through the epigenetic induction of the cell cycle inhibitor p15 through the trimethylation of histone H3K27 associated with the promoter region of p15. In ARPCs knock-out for HOTAIR p15 increased significantly (Fold increase = 3; P < 0.005) and the H3K27me3 in the promoter of p15 was less enriched (Fold decrease = 1.5; P < 0.05), leading to the increase of the cell cycle inhibitor and cell senescence.
CONCLUSION
These data demonstrated that HOTAIR regulates the self-renewal capacity of ARPCs and prevents them from becoming senescent in the short term. Moreover, HOTAIR influences ARPC ability to secrete high levels of α-Klotho, and those renal progenitors, through α-Klotho secretion, are able to influence its levels in surrounding tissues and to modulate, therefore, kidney ageing.
Anticoagulation for Ablation of Atrial Fibrillation
Introduction
Appropriate activated clotting time (ACT) during catheter ablation of atrial fibrillation (CA‐AF) is essential to minimize ...periprocedural complications.
Methods and Results
An electronic search was performed using major databases. Outcomes were thromboembolic (TE) and bleeding complications according to ACT levels (seconds). Heparin dose (U/kg) and time (minutes) to achieve the target ACT was compared among patients receiving vitamin K antagonist (VKA) versus non‐VKA oral anticoagulants (NOAC). Nineteen studies involving 7,150 patients were identified. Patients with ACT > 300 had less TE (OR, 0.51; 95% CI 0.35–0.74) and bleeding (OR, 0.70; 95% CI 0.60–0.83) compared to ACT < 300, when using any type of oral anticoagulation. The use of VKA was associated with reduced heparin requirements (mean dose: 157 U/kg vs. 209 U/kg, P < 0.03; SDM –0.86 95% CI –1.39 to –0.33), and with lower time to achieve the target ACT (mean time: 24 minutes vs. 49 minutes, P < 0.03; SDM –11.02 95% CI –13.29 to –8.75) compared to NOACs. No significant publication bias was found.
Conclusions
Performing CA‐AF with a target ACT > 300 decreases the risk of TE without increasing the risk of bleeding. Patients receiving VKAs required less heparin and reached the target ACT faster compared to NOACs.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
We report on gravitational wave discoveries from compact binary coalescences detected by Advanced LIGO and Advanced Virgo in the first half of the third observing run (O3a) between 1 April 2019 15:00 ...UTC and 1 October 2019 15:00 UTC. By imposing a false-alarm-rate threshold of two per year in each of the four search pipelines that constitute our search, we present 39 candidate gravitational wave events. At this threshold, we expect a contamination fraction of less than 10%. Of these, 26 candidate events were reported previously in near real-time through GCN Notices and Circulars; 13 are reported here for the first time. The catalog contains events whose sources are black hole binary mergers up to a redshift of ~ 0.8, as well as events whose components could not be unambiguously identified as black holes or neutron stars. For the latter group, we are unable to determine the nature based on estimates of the component masses and spins from gravitational wave data alone. The range of candidate event masses which are unambiguously identified as binary black holes (both objects ≥ 3 M⨀) is increased compared to GWTC-1, with total masses from ∼ 14M⨀ for GW190924 021846 to ∼ 150M⨀ for GW190521. For the first time, this catalog includes binary systems with significantly asymmetric mass ratios, which had not been observed in data taken before April 2019. We also find that 11 of the 39 events detected since April 2019 have positive effective inspiral spins under our default prior (at 90% credibility), while none exhibit negative effective inspiral spin. Given the increased sensitivity of Advanced LIGO and Advanced Virgo, the detection of 39 candidate events in ∼26 weeks of data (∼1.5 per week) is consistent with GWTC-1.
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We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention ...of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star–black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of
10
5
,
10
6
,
10
7
Mpc
3
for binary neutron star, neutron star–black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of
1
-
1
+
12
(
10
-
10
+
52
) for binary neutron star mergers, of
0
-
0
+
19
(
1
-
1
+
91
) for neutron star–black hole mergers, and
17
-
11
+
22
(
79
-
44
+
89
) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.
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