The detection of astrophysical ντ is an important verification of the observed flux of high-energy neutrinos. A flavour ratio of approximately νe : νμ : ντ ≈ 1 : 1 : 1 is predicted for astrophysical ...neutrinos measured at Earth due to neutrino oscillations. On top of this, the ντ offers a unique channel for neutrino astronomy due to absence of an atmospheric ντ background contribution. When a ντ interacts it produces a particle cascade and often a τ lepton which in turn decays mainly into another cascade. This results in a double cascade signature. An excellent angular resolution can be achieved when both cascade vertices are reconstructed. The KM3NeT/ARCA detector, which is under construction in the Mediterranean sea, will be able to detect this signature due to its timing and spatial resolution for cascades. We will discuss the dedicated reconstruction algorithm and performance for reconstructing double cascades using KM3NeT. The angular deviation reaches sub-degree level for tau lengths larger than 25 meters.
Interactions of cosmic ray protons, atomic nuclei, and electrons in the interstellar medium in the inner part of the Milky Way produce a γ-ray flux from the Galactic Ridge. If the γ-ray emission is ...dominated by proton and nuclei interactions, a neutrino flux comparable to the γ-ray flux is expected from the same sky region.
Data collected by the ANTARES neutrino telescope are used to constrain the neutrino flux from the Galactic Ridge in the 1-100 TeV energy range. Neutrino events reconstructed both as tracks and showers are considered in the analysis and the selection is optimized for the search of an excess in the region |l|<30°, |b|<2°. The expected background in the search region is estimated using an off-zone region with similar sky coverage. Neutrino signal originating from a power-law spectrum with spectral index ranging from Γν=1 to 4 is simulated in both channels. The observed energy distributions are fitted to constrain the neutrino emission from the Ridge.
The energy distributions in the signal region are inconsistent with the background expectation at ∼96% confidence level. The mild excess over the background is consistent with a neutrino flux with a power law with a spectral index 2.45−0.34+0.22 and a flux normalization dNνdEν=4.0−2.0+2.7×10−16 GeV−1cm−2s−1sr−1 at 40 TeV reference energy. Such flux is consistent with the expected neutrino signal if the bulk of the observed γ-ray flux from the Galactic Ridge originates from interactions of cosmic ray protons and nuclei with a power-law spectrum extending well into the PeV energy range.
Introduction. Morquio syndrome or mucopolysaccharidosis (MPS) type IV is a rare autosomal recessive lysosomal storage disease, characterized by abnormal metabolism of glycosaminoglycans associated ...with specific skeletal deformities, also known as dysostosis multiplex. Case Presentation. We present the case of a 23-year-old patient with advanced osteonecrosis of the femoral head (ONFH) on both sides due to Morquio syndrome. A diagnosis of mucopolysaccharidosis type IVB was made after extensive genetic profiling. The patient had the condition for a long time. At 7 years old, the patient was treated with bilateral pelvic Salter’s osteotomy. Afterward, the patient was able to walk freely but could never take part in sports. At 22 years old, pain in the hip increased, and magnetic resonance imaging showed a bilateral femur head necrosis. Hence, the patient underwent cementless total hip arthroplasty (THA). Intraoperatively, a periprosthetic fracture occurred. Therefore, revision surgery with internal fixation was performed on the next day. Postoperatively, a weight-bearing restriction of 20 kg on the left leg was imposed for 6 weeks. The patient made a full recovery and was able to move without residual complaints. Annual orthopedic evaluation in patients treated with surgical intervention is recommended. Discussion. Orthopedic challenges for mucopolysaccharidoses and corresponding bone alterations, known as dysostosis multiplex, involving trunk and limbs with typical radiological findings have been well described. The hip is invariably involved, with dysplasia affecting the femoral neck (coxa valga), femoral epiphysis (loss of sphericity, osteonecrosis), and a flared hypoplastic iliac wing. Symptomatic therapy consists, on the one hand, of a surgical procedure and, on the other hand, a variety of supportive measures. However, the management of joint replacement in lysosomal storage diseases has not been well reported. All patients with MPS should be considered at high risk for surgical intervention requiring anesthesia because of airway and cardiac disease manifestations. In the case of a need for THA, we recommend cemented stem fixation because of the overall poor bone quality in patients with Morquio syndrome.
24 hours stay after hip replacement Van Den Eeden, Yannick N T; De Turck, Bruno J G; Van Den Eeden, Frank M C
Acta orthopaedica,
01/2017, Letnik:
88, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Background and purpose - The length of stay after total hip arthroplasty has been reduced to 2-4 days after implementing fast-track surgery. We investigated whether a new time-based patient-centered ...primary direct anterior approach (DAA) total hip arthroplasty (THA) treatment protocol in a specialized clinic, with a planned length of stay of about 24 hours, could be achieved in all patients or only in a selected group of patients.
Patients and methods - We analyzed prospectively collected data in a cohort of 378 consecutive patients who underwent a primary direct anterior THA as a patient-centered time-based procedure between March 1, 2012 and December 31, 2015. Patients with complicated medical comorbidity and those over the age of 85 were excluded from the study. The average length of stay was recorded and all complications, re-admissions, and reoperations were registered and analyzed. The primary outcome measures were length of stay and complication rate, at discharge and 90 days postoperatively.
Results - The average length of stay for all patients was 26 hours. All patients were discharged from the clinic on the day after the operation and were able to continue their recovery at home or in a rehabilitation facility. The overall complication rate within 3 months of surgery was 6%. The 3-month re-admission rate and the 3-month reoperation rate were both 2%.
Interpretation - Performing a time-based, patient-centered fast-track program for DAA total hip arthroplasty can result in a standardized length of stay of about 24 hours and a high level of patient satisfaction with few complications, re-admissions, and reoperations.
Celotno besedilo
Dostopno za:
DOBA, FSPLJ, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
The KM3NeT research infrastructure is under construction in the Mediterranean Sea. It consists of two water Cherenkov neutrino detectors, ARCA and ORCA, aimed at neutrino astrophysics and oscillation ...research, respectively. Instrumenting a large volume of sea water with
∼
6200
optical modules comprising a total of
∼
200
,
000
photomultiplier tubes, KM3NeT will achieve sensitivity to
∼
10
MeV
neutrinos from Galactic and near-Galactic core-collapse supernovae through the observation of coincident hits in photomultipliers above the background. In this paper, the sensitivity of KM3NeT to a supernova explosion is estimated from detailed analyses of background data from the first KM3NeT detection units and simulations of the neutrino signal. The KM3NeT observational horizon (for a
5
σ
discovery) covers essentially the Milky-Way and for the most optimistic model, extends to the Small Magellanic Cloud (
∼
60
kpc
). Detailed studies of the time profile of the neutrino signal allow assessment of the KM3NeT capability to determine the arrival time of the neutrino burst with a few milliseconds precision for sources up to 5–8 kpc away, and detecting the peculiar signature of the
standing accretion shock instability
if the core-collapse supernova explosion happens closer than 3–5 kpc, depending on the progenitor mass. KM3NeT’s capability to measure the neutrino flux spectral parameters is also presented.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
KM3NeT is a research infrastructure located in the Mediterranean Sea, that will consist of two deep-sea Cherenkov neutrino detectors. With one detector (ARCA), the KM3NeT Collaboration aims at ...identifying and studying TeV–PeV astrophysical neutrino sources. With the other detector (ORCA), the neutrino mass ordering will be determined by studying GeV-scale atmospheric neutrino oscillations. The first KM3NeT detection units were deployed at the Italian and French sites between 2015 and 2017. In this paper, a description of the detector is presented, together with a summary of the procedures used to calibrate the detector in-situ. Finally, the measurement of the atmospheric muon flux between 2232–3386 m seawater depth is obtained.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The KM3NeT Collaboration is currently constructing a multi-site high-energy neutrino telescope in the Mediterranean Sea consisting of matrices of pressure-resistant glass spheres, each holding a set ...of 31 small-area photomultipliers. The main goals of the telescope are the observation of neutrino sources in the Universe and the measurement of the neutrino oscillation parameters with atmospheric neutrinos. A relative time synchronisation between photomultipliers of the nanosecond order needed to guarantee the required angular resolution of the detector. Due to the large detector volumes to be instrumented by KM3NeT, a cost reduction of the different systems is a priority. To this end, the inexpensive Nanobeacon has been designed and developed by the KM3NeT Collaboration to be used for detector time-calibration studies. At present, more than 600 Nanobeacons have been already produced. The characterisation of the optical pulse and the wavelength emission profile of the devices is critical for the time calibration. The optical pulse rise time has been quantified as less than 3 ns, while the Full Width Half Maximum is less than 6 ns. The wavelength drift, due to a variation of the supply voltage, has also been qualified as lower than 10 nm for the full range of the Nanobeacon. In this paper, more details about the main features of the Nanobeacon design, production and operation, together with the main properties of the light pulse generated are described.
KM3NeT/ARCA is a Cherenkov neutrino telescope under construction in the Mediterranean sea, optimised for the detection of astrophysical neutrinos with energies above ∼1 TeV. In this work, using Monte ...Carlo simulations including all-flavour neutrinos, the integrated and differential sensitivities for KM3NeT/ARCA are presented considering the case of a diffuse neutrino flux as well as extended and point-like neutrino sources. This analysis is applied to Starburst Galaxies demonstrating that the detector has the capability of tracing TeV neutrinos from these sources. Remarkably, after eight years, a hard power-law spectrum from the nearby Small Magellanic Cloud can be constrained. The sensitivity and discovery potential for NGC 1068 is also evaluated showing that KM3NeT/ARCA will discriminate between different astrophysical components of the measured neutrino flux after 3 years of data taking.
Abstract
On 2019 October 1, the IceCube Collaboration detected a muon track neutrino with a high probability of being of astrophysical origin, IC191001A. After a few hours, the tidal disruption event ...(TDE) AT2019dsg, observed by the Zwicky Transient Facility (ZTF), was indicated as the most likely counterpart of the IceCube track. More recently, the follow-up campaign of the IceCube alerts by ZTF suggested a second TDE, AT2019fdr, as a promising counterpart of another IceCube muon track candidate, IC200530A, detected on 2020 May 30. Here, these intriguing associations are followed-up by searching for neutrinos in the ANTARES detector from the directions of AT2019dsg and AT2019fdr using a time-integrated approach. As no significant evidence for space clustering is found in the ANTARES data, upper limits on the one-flavor neutrino flux and fluence are set.
Abstract
Since 2015 the LIGO and Virgo interferometers have detected gravitational waves from
almost one hundred coalescences of compact objects (black holes and neutron stars). This article
presents ...the results of a search performed with data from the ANTARES telescope to identify
neutrino counterparts to the gravitational wave sources detected during the third LIGO/Virgo
observing run and reported in the catalogues GWTC-2, GWTC-2.1, and GWTC-3. This search is
sensitive to all-sky neutrinos of all flavours and of energies > 100 GeV,
thanks to the inclusion of both track-like events (mainly induced by
ν
μ
charged-current
interactions) and shower-like events (induced by other interaction types). Neutrinos are selected
if they are detected within ± 500 s from the GW merger and with a reconstructed
direction compatible with its sky localisation. No significant excess is found for any of the 80
analysed GW events, and upper limits on the neutrino emission are derived. Using the information
from the GW catalogues and assuming isotropic emission, upper limits on the total energy
E
tot,
ν
emitted as neutrinos of all flavours and on the ratio
f
ν
=
E
tot,
ν
/
E
GW
between neutrino and GW emissions are also computed. Finally, a stacked
analysis of all the 72 binary black hole mergers (respectively the 7 neutron star-black hole
merger candidates) has been performed to constrain the typical neutrino emission within this
population, leading to the limits:
E
tot,
ν
< 4.0 × 10
53
erg and
f
ν
< 0.15
(respectively,
E
tot,
ν
< 3.2 × 10^53 erg and
f
ν
< 0.88) for
E
-2
spectrum
and isotropic emission. Other assumptions including softer spectra and non-isotropic scenarios
have also been tested.
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