2,185 research outputs found
Analysis of the Lepton Mixing Matrix in the Two Higgs Doublet Model
In the theoretical framework of Two Higgs Doublet Model (2HDM) plus three right-handed neutrinos we consider a universal treatment for the mass matrices, aside from that the active neutrinos acquire their small mass through the type-I seesaw mechanism. Then, as long as a matrix with four-zero texture is used to represent the right-handed neutrinos and Yukawa matrices, we obtain a unified treatment where all fermion mass matrices have four-zero texture. We obtain analytical and explicit expressions for the lepton flavour mixing matrix PMNS in terms of fermion masses and parameters associated with the 2HDM-III. Further, we compare these expressions of the PMNS matrix with the most up to date values of masses and mixing in the lepton sector, via a likelihood test. We find that the analytical expressions that we derived reproduce remarkably well the most recent experimental data of neutrino oscillations
The Usefulness of Intraoperative Cerebral C-Arm CT Angiogram for Implantation of Intracranial Depth Electrodes in Stereotactic Electroencephalography Procedure
Background: Stereotactic electroencephalography (SEEG) is an invasive diagnostic tool for localizing the epileptic zone in patients with medically refractory focal epilepsy. Despite technical and imaging advances in guiding the electrode placement, vascular injury is still one of its most serious complications. Object: To investigate the usefulness of intraoperative cerebral C-arm CT angiogram (CCTA) in avoiding intracranial hemorrhagic complications during SEEG electrode implantation. Methods: Trajectory data from 12 patients who underwent SEEG electrode implantation were studied in detail. This included an analysis of the implantation of 146 SEEG electrodes, which were guided by intraoperative CCTA, as well as the standard planning based on preoperative contrast-enhanced MRI. In addition, a prospective analysis of SEEG hemorrhagic complications using the studied methodology was performed in a total of 87 patients receiving 1,310 electrodes. Results: There was no complication related to the CCTA itself. Intraoperative CCTA entailed modification of the original trajectory based on the preoperative MRI in 27 of 146 electrode implantations (18.5%). In 10 of them, a severe vascular complication was adverted by intraoperative CCTA. The safety of this new approach was also confirmed by the analysis of postinterventional CT, which revealed a symptomatic hematoma caused by 1 single electrode out of the 1,310 implanted. Conclusions: This study showed that intraoperative CCTA in addition to preoperative MRI is useful in guiding a safer SEEG electrode implantation. The combination of both imaging modalities essentially minimizes the risk of serious hemorrhagic complications
A Causal Discovery Approach To Learn How Urban Form Shapes Sustainable Mobility Across Continents
Global sustainability requires low-carbon urban transport systems, shaped by
adequate infrastructure, deployment of low-carbon transport modes and shifts in
travel behavior. To adequately implement alterations in infrastructure, it's
essential to grasp the location-specific cause-and-effect mechanisms that the
constructed environment has on travel. Yet, current research falls short in
representing causal relationships between the 6D urban form variables and
travel, generalizing across different regions, and modeling urban form effects
at high spatial resolution. Here, we address all three gaps by utilizing a
causal discovery and an explainable machine learning framework to detect urban
form effects on intra-city travel based on high-resolution mobility data of six
cities across three continents. We show that both distance to city center,
demographics and density indirectly affect other urban form features. By
considering the causal relationships, we find that location-specific influences
align across cities, yet vary in magnitude. In addition, the spread of the city
and the coverage of jobs across the city are the strongest determinants of
travel-related emissions, highlighting the benefits of compact development and
associated benefits. Differences in urban form effects across the cities call
for a more holistic definition of 6D measures. Our work is a starting point for
location-specific analysis of urban form effects on mobility behavior using
causal discovery approaches, which is highly relevant for city planners and
municipalities across continents.Comment: 22 pages, 13 figures, 4 table
S_3-flavour symmetry as realized in lepton flavour violating processes
A variety of lepton flavour violating effects related to the recent discovery
of neutrino oscillations and mixings is here systematically discussed in terms
of an S_3-flavour permutational symmetry. After a brief review of some relevant
results on lepton masses and mixings, that had been derived in the framework of
a Minimal S_3-Invariant Extension of the Standard Model, we derive explicit
analytical expressions for the matrices of the Yukawa couplings and compute the
branching ratios of some selected flavour changing neutral current (FCNC)
processes, as well as, the contribution of the exchange of neutral flavour
changing scalars to the anomaly of the muon's magnetic moment as functions of
the masses of the charged leptons and the neutral Higgs bosons. We find that
the S_3 x Z_2 flavour symmetry and the strong mass hierarchy of the charged
leptons strongly suppress the FCNC processes in the leptonic sector well below
the present experimental upper bounds by many orders of magnitude. The
contribution of FCNC to the anomaly of the muon's magnetic moment is small but
non-negligible.Comment: 23 pages, one figure. To appear in J. Phys A: Mathematical and
Theoretical (SPE QTS5
Genera of phytopathogenic fungi: GOPHY 3
This paper represents the third contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions, information about the pathology, distribution, hosts and disease symptoms for the treated genera, as well as primary and secondary DNA barcodes for the currently accepted species included in these. This third paper in the GOPHY series treats 21 genera of phytopathogenic fungi and their relatives including: Allophoma, Alternaria, Brunneosphaerella, Elsinoe, Exserohilum, Neosetophoma, Neostagonospora, Nothophoma, Parastagonospora, Phaeosphaeriopsis, Pleiocarpon, Pyrenophora, Ramichloridium, Seifertia, Seiridium, Septoriella, Setophoma, Stagonosporopsis, Stemphylium, Tubakia and Zasmidium. This study includes three new genera, 42 new species, 23 new combinations, four new names, and three typifications of older names
Multi-module microwave assembly for fast read-out and charge noise characterization of silicon quantum dots
Fast measurements of quantum devices is important in areas such as quantum
sensing, quantum computing and nanodevice quality analysis. Here, we develop a
superconductor-semiconductor multi-module microwave assembly to demonstrate
charge state readout at the state-of-the-art. The assembly consist of a
superconducting readout resonator interfaced to a silicon-on-insulator (SOI)
chiplet containing quantum dots (QDs) in a high- nanowire transistor.
The superconducting chiplet contains resonant and coupling elements as well as
filters that, when interfaced with the silicon chip, result in a resonant
frequency ~GHz, a loaded quality factor , and a resonator
impedance ~. Combined with the large gate lever arms of SOI
technology, we achieve a minimum integration time for single and double QD
transitions of 2.77~ns and 13.5~ns, respectively. We utilize the assembly to
measure charge noise over 9 decades of frequency up to 500~kHz and find a 1/
dependence across the whole frequency spectrum as well as a charge noise level
of 4~eV/ at 1~Hz. The modular microwave circuitry
presented here can be directly utilized in conjunction with other quantum
device to improve the readout performance as well as enable large bandwidth
noise spectroscopy, all without the complexity of superconductor-semiconductor
monolithic fabrication.Comment: Main: 7 pages, 4 figures. Supplementary: 6 pages, 5 figure
FASER: ForwArd Search ExpeRiment at the LHC
FASER, the ForwArd Search ExpeRiment, is a proposed experiment dedicated to
searching for light, extremely weakly-interacting particles at the LHC. Such
particles may be produced in the LHC's high-energy collisions in large numbers
in the far-forward region and then travel long distances through concrete and
rock without interacting. They may then decay to visible particles in FASER,
which is placed 480 m downstream of the ATLAS interaction point. In this work,
we describe the FASER program. In its first stage, FASER is an extremely
compact and inexpensive detector, sensitive to decays in a cylindrical region
of radius R = 10 cm and length L = 1.5 m. FASER is planned to be constructed
and installed in Long Shutdown 2 and will collect data during Run 3 of the 14
TeV LHC from 2021-23. If FASER is successful, FASER 2, a much larger successor
with roughly R ~ 1 m and L ~ 5 m, could be constructed in Long Shutdown 3 and
collect data during the HL-LHC era from 2026-35. FASER and FASER 2 have the
potential to discover dark photons, dark Higgs bosons, heavy neutral leptons,
axion-like particles, and many other long-lived particles, as well as provide
new information about neutrinos, with potentially far-ranging implications for
particle physics and cosmology. We describe the current status, anticipated
challenges, and discovery prospects of the FASER program.Comment: 13 pages, 4 figures, submitted as Input to the European Particle
Physics Strategy Update 2018-2020 and draws on FASER's Letter of Intent,
Technical Proposal, and physics case documents (arXiv:1811.10243,
arXiv:1812.09139, and arXiv:1811.12522
Extracellular vesicles in hepatology: Physiological role, involvement in pathogenesis, and therapeutic opportunities.
Since the first descriptions of hepatocyte-released exosome-like vesicles in 2008, the number of publications describing Extracellular Vesicles (EVs) released by liver cells in the context of hepatic physiology and pathology has grown exponentially. This growing interest highlights both the importance that cell-to-cell communication has in the organization of multicellular organisms from a physiological point of view, as well as the opportunity that these circulating organelles offer in diagnostics and therapeutics. In the present review, we summarize systematically and comprehensively the myriad of works that appeared in the last decade and lighted the discussion about the best opportunities for using EVs in liver disease therapeutics
- …