1,331 research outputs found
Quantile forecast discrimination ability and value
While probabilistic forecast verification for categorical forecasts is well
established, some of the existing concepts and methods have not found their
equivalent for the case of continuous variables. New tools dedicated to the
assessment of forecast discrimination ability and forecast value are introduced
here, based on quantile forecasts being the base product for the continuous
case (hence in a nonparametric framework). The relative user characteristic
(RUC) curve and the quantile value plot allow analysing the performance of a
forecast for a specific user in a decision-making framework. The RUC curve is
designed as a user-based discrimination tool and the quantile value plot
translates forecast discrimination ability in terms of economic value. The
relationship between the overall value of a quantile forecast and the
respective quantile skill score is also discussed. The application of these new
verification approaches and tools is illustrated based on synthetic datasets,
as well as for the case of global radiation forecasts from the high resolution
ensemble COSMO-DE-EPS of the German Weather Service
Red Yeast Rice for the Improvement of Lipid Profiles in Mild-to-Moderate Hypercholesterolemia: A Narrative Review
Reducing low-density lipoprotein cholesterol (LDL-C) levels is a key target for lowering cardiovascular risk and preventing atherosclerotic cardiovascular disease (ASCVD). Red yeast rice (RYR) is a nutraceutical widely used as a lipid-lowering dietary supplement. The main cholesterol-lowering components of RYR are monacolins, particularly monacolin K, which is structurally identical to lovastatin and targets the same key enzyme of cholesterol biosynthesis. RYR supplementation reduces LDL-C levels by approximately 15-34% versus placebo, with a similar effect to low-dose, first-generation statins in subjects with mild-to-moderate dyslipidemia. RYR has also demonstrated beneficial reductions of up to 45% versus placebo in the risk of ASCVD events in secondary prevention studies. RYR at a dose that provides about 3 mg/d of monacolin K is well tolerated, with an adverse event profile similar to that of low-dose statins. RYR is therefore a treatment option for lowering LDL-C levels and ASCVD risk for people with mild-to-moderate hypercholesterolemia who are ineligible for statin therapy, particularly those who are unable to implement lifestyle modifications, and also for people who are eligible for statin therapy but who are unwilling to take a pharmacologic therapy
Monopolin subunit Csm1 associates with MIND complex to establish monopolar attachment of sister kinetochores at meiosis I
Sexually reproducing organisms halve their cellular ploidy during gametogenesis by undergoing a specialized form of cell division known as meiosis. During meiosis, a single round of DNA replication is followed by two rounds of nuclear divisions (referred to as meiosis I and II). While sister kinetochores bind to microtubules emanating from opposite spindle poles during mitosis, they bind to microtubules originating from the same spindle pole during meiosis I. This phenomenon is referred to as mono-orientation and is essential for setting up the reductional mode of chromosome segregation during meiosis I. In budding yeast, mono-orientation depends on a four component protein complex referred to as monopolin which consists of two nucleolar proteins Csm1 and Lrs4, meiosis-specific protein Mam1 of unknown function and casein kinase Hrr25. Monopolin complex binds to kinetochores during meiosis I and prevents bipolar attachments. Although monopolin associates with kinetochores during meiosis I, its binding site(s) on the kinetochore is not known and its mechanism of action has not been established. By carrying out an imaging-based screen we have found that the MIND complex, a component of the central kinetochore, is required for monopolin association with kinetochores during meiosis. Furthermore, we demonstrate that interaction of monopolin subunit Csm1 with the N-terminal domain of MIND complex subunit Dsn1, is essential for both the association of monopolin with kinetochores and for monopolar attachment of sister kinetochores during meiosis I. As such this provides the first functional evidence for a monopolin-binding site at the kinetochore
Evidence for a role of TRIB3 in the regulation of megakaryocytopoiesis
Megakaryocytopoiesis is a complex differentiation process driven by the hormone
thrombopoietin by which haematopoietic progenitor cells give rise to
megakaryocytes, the giant bone marrow cells that in turn break down to form blood
platelets. The Tribbles Pseudokinase 3 gene (TRIB3) encodes a pleiotropic protein
increasingly implicated in the regulation of cellular differentiation programmes.
Previous studies have hinted that TRIB3 could be also involved in
megakaryocytopoiesis but its role in this process has so far not been investigated.
Using cellular model systems of haematopoietic lineage differentiation here we
demonstrate that TRIB3 is a negative modulator of megakaryocytopoiesis. We found
that in primary cultures derived from human haematopoietic progenitor cells,
thrombopoietin-induced megakaryocytic differentiation led to a time and dosedependent
decrease in TRIB3 mRNA levels. In the haematopoietic cell line UT7/mpl,
silencing of TRIB3 increased basal and thrombopoietin-stimulated megakaryocyte
antigen expression, as well as basal levels of ERK1/2 phosphorylation. In primary
haematopoietic cell cultures, silencing of TRIB3 facilitated megakaryocyte
differentiation. In contrast, over-expression of TRIB3 in these cells inhibited the
differentiation process. The in-vitro identification of TRIB3 as a negative regulator of
megakaryocytopoiesis suggests that in-vivo this gene could be important for the
regulation of platelet production
A discrete firefly algorithm to solve a rich vehicle routing problem modelling a newspaper distribution system with recycling policy
A real-world newspaper distribution problem with recycling policy is tackled in this work. In order to meet all the complex restrictions contained in such a problem, it has been modeled as a rich vehicle routing problem, which can be more specifically considered as an asymmetric and clustered vehicle routing problem with simultaneous pickup and deliveries, variable costs and forbidden paths (AC-VRP-SPDVCFP). This is the first study of such a problem in the literature. For this reason, a benchmark composed by 15 instances has been also proposed. In the design of this benchmark, real geographical positions have been used, located in the province of Bizkaia, Spain. For the proper treatment of this AC-VRP-SPDVCFP, a discrete firefly algorithm (DFA) has been developed. This application is the first application of the firefly algorithm to any rich vehicle routing problem. To prove that the proposed DFA is a promising technique, its performance has been compared with two other well-known techniques: an evolutionary algorithm and an evolutionary simulated annealing. Our results have shown that the DFA has outperformed these two classic meta-heuristics
The Milliarcsecond Structure of Radio Galaxies and Quasars
Hybrid maps of the nuclei of radio galaxies and quasars show a variety of morphologies. Among compact sources, two structures are common: an asymmetric, “core-jet” morphology (eg, 3C 273), and an “equal double” morphology with two separated, similar components (eg, CTD 93). The nuclei of extended, double radio galaxies generally have a core-jet morphology with the jet directed toward one of the outer components
Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV
A search for pair-produced charged Higgs bosons is performed with the L3
detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV,
corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a
charm and a strange quark or into a tau lepton and its associated neutrino are
considered. The observed events are consistent with the expectations from
Standard Model background processes. A lower limit of 65.5 GeV on the charged
Higgs mass is derived at 95 % confidence level, independent of the decay
branching ratio Br(H^{+/-} -> tau nu)
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos2Δϕ modulation for all ΣETPb ranges and particle pT
Competitive and Cooperative Interactions Mediate RNA Transfer from Herpesvirus Saimiri ORF57 to the Mammalian Export Adaptor ALYREF
The essential herpesvirus adaptor protein HVS ORF57, which has homologs in all other herpesviruses, promotes viral mRNA
export by utilizing the cellular mRNA export machinery. ORF57 protein specifically recognizes viral mRNA transcripts, and
binds to proteins of the cellular transcription-export (TREX) complex, in particular ALYREF. This interaction introduces viral
mRNA to the NXF1 pathway, subsequently directing it to the nuclear pore for export to the cytoplasm. Here we have used a
range of techniques to reveal the sites for direct contact between RNA and ORF57 in the absence and presence of ALYREF. A
binding site within ORF57 was characterized which recognizes specific viral mRNA motifs. When ALYREF is present, part of
this ORF57 RNA binding site, composed of an a-helix, binds preferentially to ALYREF. This competitively displaces viral RNA
from the a-helix, but contact with RNA is still maintained by a flanking region. At the same time, the flexible N-terminal
domain of ALYREF comes into contact with the viral RNA, which becomes engaged in an extensive network of synergistic
interactions with both ALYREF and ORF57. Transfer of RNA to ALYREF in the ternary complex, and involvement of individual
ORF57 residues in RNA recognition, were confirmed by UV cross-linking and mutagenesis. The atomic-resolution structure
of the ORF57-ALYREF interface was determined, which noticeably differed from the homologous ICP27-ALYREF structure.
Together, the data provides the first site-specific description of how viral mRNA is locked by a herpes viral adaptor protein in
complex with cellular ALYREF, giving herpesvirus access to the cellular mRNA export machinery. The NMR strategy used
may be more generally applicable to the study of fuzzy protein-protein-RNA complexes which involve flexible polypeptide
regions
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