The coherent photoproduction of
J
/
ψ
and
ψ
′
mesons was measured in ultra-peripheral Pb–Pb collisions at a center-of-mass energy
s
NN
=
5.02
TeV with the ALICE detector. Charmonia are detected in ...the central rapidity region for events where the hadronic interactions are strongly suppressed. The
J
/
ψ
is reconstructed using the dilepton (
l
+
l
-
) and proton–antiproton decay channels, while for the
ψ
′
the dilepton and the
l
+
l
-
π
+
π
-
decay channels are studied. The analysis is based on an event sample corresponding to an integrated luminosity of about 233
μ
b
-
1
. The results are compared with theoretical models for coherent
J
/
ψ
and
ψ
′
photoproduction. The coherent cross section is found to be in a good agreement with models incorporating moderate nuclear gluon shadowing of about 0.64 at a Bjorken-
x
of around
6
×
10
-
4
, such as the EPS09 parametrization, however none of the models is able to fully describe the rapidity dependence of the coherent
J
/
ψ
cross section including ALICE measurements at forward rapidity. The ratio of
ψ
′
to
J
/
ψ
coherent photoproduction cross sections was also measured and found to be consistent with the one for photoproduction off protons.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The freshwater snail Biomphalaria glabrata possesses a diverse family of fibrinogen-related proteins (FREPs), hemolymph polypeptides that consist of one or two amino-terminal immunoglobulin ...superfamily (IgSF) domains and a carboxyl-terminal fibrinogen domain. Here, we show that the IgSF1 domain of the FREP3 subfamily is diversified at the genomic level at higher rates than those recorded for control genes. All sequence variants are derived from a small set of nine source sequences by point mutation and recombinatorial processes. Diverse FREP3 transcripts are also produced. We hypothesize a mechanism present in snails that is capable of diversifying molecules involved in internal defense.
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We describe a new interface for a prototype quadrupole–quadrupole-time-of-flight (TOF) mass spectrometer (Centaur, Sciex) that allows rapid switching between electrospray ionization (ESI) and ...matrix-assisted laser desorption/ionization (MALDI) modes of operation. Instrument performance in both modes is comparable (i.e., resolution ∼10,000 FWHM, mass accuracy <10 ppm, sensitivity ∼1 fmol) because the ion source is decoupled from the TOF mass analyzer by extensive gas collisions in the quadrupole stages of the instrument. The capacity to obtain side-by-side high quality ESI and MALDI mass spectra from a single proteolytic mixture greatly facilitates the identification of proteins and elucidation of their primary structures. Improved strategies for protein identification result from this ability to measure spectra using both ionization modes in the same instrument and to perform MS/MS on singly charged as well as multiply charged ions. Examples are provided to demonstrate the utility and performance of the modified instrument.
If dark matter has mass lower than around 1 GeV, it will not impart enough energy to cause detectable nuclear recoils in many direct-detection experiments. However, if dark matter is upscattered to ...high energy by collisions with cosmic rays, it may be detectable in both direct-detection experiments and neutrino experiments. We report the results of a dedicated search for boosted dark matter upscattered by cosmic rays, using ~14.6 solar days of data from the PROSPECT reactor antineutrino experiment. We show that such a flux of upscattered dark matter would display characteristic diurnal sidereal modulation, and use this to set new experimental constraints on sub-GeV dark matter exhibiting large interaction cross sections.
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High impedance faults (HIFs) on overhead power lines are known to cause fires. They are difficult to detect using conventional protection relays because the fault current is insufficient to cause ...tripping. The delay in detecting HIFs can result in severe bushfires and energy losses; hence a high throughput, low latency detection scheme needs to be developed for HIF detection. Moreover, the complexities associated with HIF detection demands signal processing techniques combined with artificial intelligence to achieve higher detection accuracy. This paper proposes a sustainable deep learning-based approach in an edge device, that can be mounted on top of a power pole to detect HIFs in real-time. Data acquisition, feature extraction, and deep learning based fault identification are performed in an embedded edge node to achieve higher throughput, reduced latency as well as offload the network traffic. Furthermore, optimization techniques such as hardware parallelism and pipelining are adapted to achieve real-time fault identification on edge devices while ensuring the efficient usage of its limited resources. Real-time implementation of the proposed system is validated through laboratory experiments and the results demonstrate the suitability of edge computing to detect HIFs in terms of reduced detection latency (115.2 ms) and higher detection accuracy (98.67 percent).
The Nd:(LuxGd1−x)3Ga5O12 (Nd:LGGG) laser operating at 1329 nm in both the continuous wave (CW) and the passively Q-switched (PQS) regimes has been successfully demonstrated. With an absorbed pump ...power of 18.8 W, a maximum CW output power of 3.7 W was obtained, corresponding to an optical-optical conversion efficiency of 19.6% and a slope efficiency of 20.9%. The PQS laser performance was obtained using a V3+:YAG crystal as the saturable absorber. The maximum average output power, shortest pulse width, largest pulse energy and highest peak power were 0.75 W, 25.9 ns, 43.6 μJ and 1.7 kW, respectively. The results indicate that a Nd:LGGG crystal with a low Lu-doping level (0.66 at.%) could be a novel potential laser gain medium suitable for laser diode pumping and PQS operation at a wavelength of 1.3 μm.
It has been suggested that reactive oxygen species may be involved in the regulation of vascular tone. However, the underlying mechanisms remain to be elucidated. The present studies were designed to ...investigate the contractile effects of hydrogen peroxide (H
2O
2), one of the reactive oxygen species, on isolated ring segments of rat aorta with and without endothelium. H
2O
2 induced an endothelium-independent contraction in isolated rat aorta ring segments in a concentration-dependent manner at concentrations from 5×10
−6 to 5×10
−3 M. H
2O
2-induced contractions of denuded rat aorta rings were stronger than those on intact rat aorta segments. The contractile effects of H
2O
2 were inhibited completely by 1200 u/ml catalase. The presence of 1.0
μM Fe
2+ or 10
μM proadifen, a cytochrome P450 monooxygenase inhibitor, potentiated the contractile effect of H
2O
2 on isolated rat aorta segments. 1 mM deferoxamine (a Fe
2+ chelator) or 100
μM dimethyl sulfoxide (a hydroxyl radical scavenger) significantly attenuated the vessel contractions induced by hydrogen peroxide plus Fe
2+ or hydrogen peroxide itself. Removal of extracellular Ca
2+ (Ca
2+
0), addition of 5
μM verapamil, administration of a protein kinase C inhibitor (staurosporine), treatment with an inhibitor of protein tyrosine phosphorylation (genistein) or employment of 5.0
μM indomethacin resulted in a significant attenuation of the contractile responses of the vessels to H
2O
2. Pharmacological antagonists (e.g. a muscarinic acetylcholine receptor antagonist (atropine), an antagonist of histamine H
1 receptors (diphenhydramine), an antagonist of histamine H
2 receptors (cimetidine), an
α-adrenoceptor antagonist (phentolamine), a
β-adrenoceptor antagonist (propranolol) and an antagonist of serotonin receptor (methysergide)) did not inhibit or attenuate the contractions induced by H
2O
2. Exposure of primary aortic smooth muscle cells to H
2O
2 (5×10
−6 to 5×10
−3 M) produced significant rises of intracellular Ca
2+ (Ca
2+
i) within 20 s. Employment of 1.0
μM Fe
2+ markedly enhanced the increment in Ca
2+
i in the smooth muscle cells. 10
μM proadifen treatment failed to alter the hydrogen peroxide-induced increment in Ca
2+
i of the smooth muscle cells. However, the presence of 5
μM indomethacin significantly attenuated the rise in Ca
2+
i in smooth muscle cells. The present results suggest that H
2O
2 can induce contractions of rat aorta segments, at pathophysiological concentrations, which are Ca
2+-dependent. Hydroxyl radicals (
·
OH
), cyclooxygenase products, protein kinase C and products of protein tyrosine phosphorylation appear to play some role in hydrogen peroxide-induced contractions. Metabolites catalyzed by cytochrome P450-dependent enzymes (upon treatment with hydrogen peroxide) appear to exert a vasodilator effect on rat aorta segments. Lastly, some unidentified mediators, produced by a cytochrome P450 inhibitor (proadifen), during hydrogen peroxide treatment, appear to play some role in contraction of vascular smooth muscle of rat aorta segments in vitro.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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