A proper canine neonatal assistance, required to reduce the high perinatal loss rate, imply a full knowledge about the fetal-to-neonatal physiology. Because fetal fluids play an important role ...throughout mammals pregnancy, influencing fetal growth and development, fetal well being, and contributing to guarantee the most suitable environment for the fetus, the knowledge about fetal fluids biochemical composition is of major importance. At first, the biochemical composition of fetal fluids collected by normal developed, healthy and viable newborns, is necessary to depict the normal features, and represent the first step for the further detection of abnormalities associated to fetal/neonatal distress and useful for the early identification of newborns needing special attention, immediately after birth. The present study was aimed to define the biochemical composition of amniotic and allantoic fluids collected from fetus delivered by caesarean section at term of pregnancy. To reduce the possible confounding effect of maternal labor or troubles at parturition, fetal fluids were collected only from puppies born by elective caesaeran section, at term of normal pregnancies. Fetal fluids from 76 puppies, 70 normal and six pathologic newborns, born by elective caesarean section were collected and analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, lactate dehydrogenase (LDH), creatine-kinase (CK), alkaline phosphatase (ALP), creatinine, urea, amylase, lipase, gamma-glutamyl transferase (γ-GT), triglycerides, cholesterol, total proteins, albumin, globulins, glucose, magnesium, potassium, chloride, sodium, calcium, phosphorus and osmolarity. No significant differences were found between biochemical composition of amniotic or allantoic fluid in normal and pathologic newborns, maybe due to the small number of the pathologic puppies. Although some correlations between the two fluids were found (albumin, phosphorus, glucose and triglycerides), the results showed significant differences between the amniotic and allantoic biochemical composition (for all the parameters, except of alanine aminotransferase, triglycerides, cholesterol, albumin, amylase and glucose), suggesting that diverse sources could concur to the final composition of each fluid. A wide variability within and among litters was found for both amniotic and allantoic biochemical composition, and for some parameters an influence of breed body size (amniotic amylase, cholesterol, and allantoic calcium and glucose), maternal parity (amniotic and allantoic CK, glucose, LDH, chloride) and newborn gender (allantoic phosphorus) was found. Further investigations are needed for addressing the origin of each fetal fluid biochemical composition in the dog and also to indeep possible differences in fetal fluids biochemical composition between normal and pathologic puppies, providing potential markers for the quick identification of newborns that need special surveillance and cares immediately after birth.
•Biochemical canine fetal fluids composition at term.•Fetal fluids from 76 puppies, 70 normal and six pathologic newborns.•Several significant differences between the amniotic and allantoic biochemical composition.•Some parameters were influenced by breed body size, maternal parity and fetal gender.•No differences between biochemical fetal fluids composition in normal and pathologic newborns.
Abstract
Core-collapse supernovae are among the most magnificent events in the observable universe. They produce many of the chemical elements necessary for life to exist and their remnants—neutron ...stars and black holes—are interesting astrophysical objects in their own right. However, despite millennia of observations and almost a century of astrophysical study, the explosion mechanism of core-collapse supernovae is not yet well understood. Hyper-Kamiokande is a next-generation neutrino detector that will be able to observe the neutrino flux from the next galactic core-collapse supernova in unprecedented detail. We focus on the first 500 ms of the neutrino burst, corresponding to the accretion phase, and use a newly-developed, high-precision supernova event generator to simulate Hyper-Kamiokande's response to five different supernova models. We show that Hyper-Kamiokande will be able to distinguish between these models with high accuracy for a supernova at a distance of up to 100 kpc. Once the next galactic supernova happens, this ability will be a powerful tool for guiding simulations toward a precise reproduction of the explosion mechanism observed in nature.
Letter of intent for KM3NeT 2.0 Adrián-Martínez, S; Aharonian, F; Aiello, S ...
Journal of physics. G, Nuclear and particle physics,
08/2016, Letnik:
43, Številka:
8
Journal Article
Recenzirano
Odprti dostop
The main objectives of the KM3NeT Collaboration are (i) the discovery and subsequent observation of high-energy neutrino sources in the Universe and (ii) the determination of the mass hierarchy of ...neutrinos. These objectives are strongly motivated by two recent important discoveries, namely: (1) the high-energy astrophysical neutrino signal reported by IceCube and (2) the sizable contribution of electron neutrinos to the third neutrino mass eigenstate as reported by Daya Bay, Reno and others. To meet these objectives, the KM3NeT Collaboration plans to build a new Research Infrastructure consisting of a network of deep-sea neutrino telescopes in the Mediterranean Sea. A phased and distributed implementation is pursued which maximises the access to regional funds, the availability of human resources and the synergistic opportunities for the Earth and sea sciences community. Three suitable deep-sea sites are selected, namely off-shore Toulon (France), Capo Passero (Sicily, Italy) and Pylos (Peloponnese, Greece). The infrastructure will consist of three so-called building blocks. A building block comprises 115 strings, each string comprises 18 optical modules and each optical module comprises 31 photo-multiplier tubes. Each building block thus constitutes a three-dimensional array of photo sensors that can be used to detect the Cherenkov light produced by relativistic particles emerging from neutrino interactions. Two building blocks will be sparsely configured to fully explore the IceCube signal with similar instrumented volume, different methodology, improved resolution and complementary field of view, including the galactic plane. One building block will be densely configured to precisely measure atmospheric neutrino oscillations.
The next generation of water Cherenkov neutrino telescopes in the Mediterranean Sea are under construction offshore France (KM3NeT/ORCA) and Sicily (KM3NeT/ARCA). The KM3NeT/ORCA detector features an ...energy detection threshold which allows to collect atmospheric neutrinos to study flavour oscillation. This paper reports the KM3NeT/ORCA sensitivity to this phenomenon. The event reconstruction, selection and classification are described. The sensitivity to determine the neutrino mass ordering was evaluated and found to be 4.4
σ
if the true ordering is normal and 2.3
σ
if inverted, after 3 years of data taking. The precision to measure
Δ
m
32
2
and
θ
23
were also estimated and found to be
85
.
10
-
6
eV
2
and
(
-
3.1
+
1.9
)
∘
for normal neutrino mass ordering and,
75
.
10
-
6
eV
2
and
(
-
7.0
+
2.0
)
∘
for inverted ordering. Finally, a unitarity test of the leptonic mixing matrix by measuring the rate of tau neutrinos is described. Three years of data taking were found to be sufficient to exclude
event rate variations larger than 20% at
3
σ
level.
Mafic alkaline magmas, such as those feeding the persistent eruptive activity of Stromboli and Mt. Etna volcanoes in Italy, are dominated by the crystallization of plagioclase via cooling and ...degassing phenomena related to the dynamics of shallow crustal reservoirs and eruptive conduits. Because plagioclase textures and compositions are extremely sensitive to the changes of intensive variables in subvolcanic plumbing systems, the phenomenological variability of erupted crystals preserves detailed evidence of complex growth histories. From this point of view, we reappraise the textural maturation and compositional complexity of plagioclase by allying thermodynamic and kinetic principles to natural and experimental observations, with the purpose of drawing up guidelines for reconstructing magma dynamics in mafic alkaline volcanic settings. A multifaceted statistical method is adopted to parameterize the decay of crystal growth rate with increasing crystallization time, as relaxation kinetics prevails over melt supersaturation effects. This model parameterization is combined with the textural analysis of natural plagioclase crystals to quantify the residence time of phenocrysts in equilibrium with magmas at Stromboli and Mt. Etna and/or the timescale of rapid microlite growth during disequilibrium ascent of magmas within the conduit. The role played by temperature and melt-water content on plagioclase components and major cation substitution mechanisms is also evaluated under both isobaric-isothermal and decompression conditions. The emerging paradigm is that the influence of dissolved water on anorthite-albite exchange between plagioclase and melt is overwhelmingly mitigated by changes in temperature at conditions of P = 30–300 MPa, T = 1050–1150 °C, fO2 = NNO + 1.9-NNO + 2.3, and melt-H2O = 0.6–4.4 wt%. As a corollary, anorthite and albite melt activities are almost fully encapsulated in the variation of anhydrous melt components as the crystallization of plagioclase proceeds during magma cooling. Following this line of reasoning, we propose an integrated modeling approach to decipher complex zoning patterns in natural plagioclase phenocrysts from mafic alkaline eruptions. Key findings from our re-assessment of equilibrium, thermometric, and hygrometric models indicate that temperature and dissolved water can be iteratively estimated for different plagioclase textural patterns if crystals are sufficiently strongly zoned and probability-based criteria are applied to determine the maximum probability distribution from kernel density analysis.
The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a hybrid photodetector. The idea, born with the purpose to use a SiPM for large detection volumes, consists in replacing ...the classical dynode chain with a special SiPM. In this configuration, we match the large sensitive area of a photocathode with the performances of the SiPM technology, which therefore acts like an electron detector and so like a current amplifier. The excellent photon counting capability, fast response, low power consumption and the stability are among the most attractive features of the VSiPMT.We now present the progress on the realization of a 1-in. prototype and the preliminary tests we are performing on it.
•The VSiPMT is a new high gain photodetector with very good photon counting capability.•Simulations to realize a good focusing system have been done.•A test bench was set up to verify the simulations.•A 1-in. VSiPMT prototype has been realized and tested, with good results.•A 1-in. industrial prototype has been realized by Hamamatsu and is now under test.
The 2-inches VSiPMT industrial prototypes Barbato, F.C.T.; Barbarino, G.; Rosa, G. De ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2020, Letnik:
958
Journal Article
Recenzirano
Photon detection is a key factor to study many physical processes in several areas of fundamental physics research. Focusing the attention on photodetectors for particle astrophysics, we understand ...that we are very close to new discoveries and new results. In order to push the progress in the study of very high-energy or extremely rare phenomena (e.g. dark matter, proton decay, neutrinos from astrophysical sources) the current and future experiments require additional improvements in linearity, gain, quantum efficiency and single photon counting capability. To meet the requirements of these classes of experiments, we propose a new design for a modern hybrid photodetector: the VSiPMT (Vacuum Silicon PhotoMultiplier Tube).
The idea is to replace the classical dynode chain of a PMT with a SiPM, which therefore acts as a single stage Geiger electron detector and amplifier, without statistical fluctuations. The aim is to match the large sensitive area of a photocathode with the performances of the SiPM technology. The previous VSiPMT prototypes already showed many attractive features such as low power consumption, very large dynamic range, excellent photon counting capability and low voltage driven gain.
We now present the results of the full characterization of the latest and largest version achieved up to now, a 2-inches VSiPMT manufactured by Hamamatsu.
•The VSiPMT is a new high gain photodetector with very good photon counting capability.•Inches prototypes have been realized in collaboration with Hamamatsu.•The prototypes have been tested with very good results.•The prototypes will be tested in a little experiment to compare their answer with both a matrix of SiPMs both a PMT.
The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a revolutionary hybrid photodetector. The idea, born with the purpose to use a SiPM for large detection volumes, consists ...in replacing the classical dynode chain with a SiPM. In this configuration, we match the large sensitive area of a photocathode with the performances of the SiPM technology, which therefore acts like an electron detector and so like a current amplifier. The excellent photon counting capability, fast response, low power consumption and great stability are among the most attractive features of the VSiPMT. In order to realize such a device we first studied the feasibility of this detector both from theoretical and experimental point of view, by implementing a Geant4-based simulation and studying the response of a special non-windowed MPPC by Hamamatsu with an electron beam. Thanks to this result Hamamatsu realized two VSiPMT industrial prototypes with a photocathode of 3mm diameter. We present the progress on the realization of a 1-inch prototype and the preliminary tests we are performing on it.
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