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By using 6.32 fbâ1 of data collected with the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, we perform an amplitude analysis of the decay D+s ! K0S +â0 and determine the relative fractions and phase differences of different intermediate processes, which include K0S (770)+, K0S (1450)+, Kâ(892)0â+, Kâ(892)+â0, and Kâ(1410)0â+. With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be B(D+s ! K0S +â0) = (5.43 ± 0.30stat ± 0.15syst) Ă 10â3.
The Born cross sections of the e+eâ â D*+D*â and e+eâ â D*+Dâ processes are measured using e+eâ collision data collected with the BESIII experiment at center-of-mass energies from 4.085 to 4.600 GeV, corresponding to an integrated luminosity of 15.7 fbâ1. The results are consistent with and more precise than the previous measurements by the Belle, Babar and CLEO collaborations. The measurements are essential for understanding the nature of vector charmonium and charmonium-like states.
We report a measurement of the observed cross sections of e+ eâ â J/ÏX based on 3.21 fb â 1 of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(Ï(3686) â J/ÏX) = (64.4 ± 0.6 ± 1.6)% and B(Ï(3770) â J/ÏX) = (0.5 ± 0.2 ± 0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays Ï (3686) â J/ÏX and Ï(3770) â J/ÏX. Instead, it can be better described with one more BW amplitude of the decay R(3760)â J/ÏX. Under this assumption, we extracted the R (3760) mass M R (3760 ) = 3766.2 ± 3.8 ± 0.4 MeV/c2, total width Î tot R ( 3760 ) = 22.2 ± 5.9 ± 1.4 MeV, and product of leptonic width and decay branching fraction
ÎeeR(3760) B[R(3760) â J/ÏX] = (79.4 ± 85.5 ± 11.7) eV. The significance of the R(3760) is 5.3Ï. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.
The process e+eââÏη is studied at 22 center-of-mass energy points (âs) between 2.00 and 3.08 GeV using 715ââpbâ1 of data collected with the BESIII detector. The measured Born cross section of e+eââÏη is found to be consistent with BABAR measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9Ï with mass (2163.5±6.2±3.0)ââMeV/c2 and width (31.1+21.1â11.6±1.1)ââMeV, where the first uncertainties are statistical and the second are systematic.
Relative fractions and phases of the intermediate decays are determined. With the detection efficiency estimated by the results of the amplitude analysis, the branching fraction of DĂŸ s â KâKĂŸÏĂŸÏ0 decay is measured to be Ă°5.42 0.10stat 0.17systĂ%.
Measurement of singly Cabibbo-suppressed decays D0âŻââŻÏ0Ï0Ï0, Ï0Ï0η, Ï0ηη and ηηη
(2018)
Using a data sample of e+eâ collision data corresponding to an integrated luminosity of 2.93 fbâ1 collected with the BESIII detector at a center-of-mass energy of s=3.773GeV, we search for the singly Cabibbo-suppressed decays D0âÏ0Ï0Ï0, Ï0Ï0η, Ï0ηη and ηηη using the double tag method. The absolute branching fractions are measured to be B(D0âÏ0Ï0Ï0)=(2.0±0.4±0.3)Ă10â4, B(D0âÏ0Ï0η)=(3.8±1.1±0.7)Ă10â4 and B(D0âÏ0ηη)=(7.3±1.6±1.5)Ă10â4 with the statistical significances of 4.8Ï, 3.8Ï and 5.5Ï, respectively, where the first uncertainties are statistical and the second ones systematic. No significant signal of D0âηηη is found, and the upper limit on its decay branching fraction is set to be B(D0âηηη)<1.3Ă10â4 at the 90% confidence level.
Using a sample of (10.09±0.04)Ă109 J/Ï events collected with the BESIII detector, a partial wave analysis of J/ÏâγηâČηâČ is performed.The masses and widths of the observed resonances and their branching fractions are reported. The main contribution is from J/ÏâÎłf0(2020) with f0(2020)âηâČηâČ, which is found with a significance of greater than 25Ï. The product branching fraction B(J/Ï â Îłf0(2020))â
B(f0(2020) â ηâČηâČ is measured to be (2.63±0.06(stat.) + 0.31â0.46(syst.))Ă10â4.
Using data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.178 to 4.600 GeV, we study the process eĂŸeâ â Ï0XĂ°3872ĂÎł and search for ZcĂ°4020Ă0 â XĂ°3872ĂÎł. We find no significant signal and set upper limits on ÏĂ°eĂŸeâ â Ï0XĂ°3872Ăγà · BĂ°XĂ°3872Ă â ÏĂŸÏâJ=ÏĂ and ÏĂ°eĂŸeâ â Ï0ZcĂ°4020Ă0à · BĂ°ZcĂ°4020Ă0 â XĂ°3872Ăγà · BĂ°XĂ°3872Ă â ÏĂŸÏâJ=ÏĂ for each energy point at 90% confidence level, which is of the order of several tenths pb.
The electromagnetic process is studied with the initial-state-radiation technique using 7.5 fbâ1 of data collected by the BESIII experiment at seven energy points from 3.773 to 4.600 GeV. The Born cross section and the effective form factor of the proton are measured from the production threshold to 3.0 GeV/ using the invariant-mass spectrum. The ratio of electric and magnetic form factors of the proton is determined from the analysis of the proton-helicity angular distribution.
We present the first experimental search for the rare charm decay D0âÏ0ÎœÂŻÎœ. It is based on an e+eâ collision sample consisting of 10.6Ă10^6 pairs of D0ÂŻD0 mesons collected by the BESIII detector at âs=3.773 GeV, corresponding to an integrated luminosity of 2.93 fb^â1. A data-driven method is used to ensure the reliability of the background modeling. No significant D0âÏ0ÎœÂŻÎœ signal is observed in data and an upper limit of the branching fraction is set to be 2.1Ă10^-4 at the 90% confidence level. This is the first experimental constraint on charmed-hadron decays into dineutrino final states.
Measurement of the branching fraction of leptonic decay D+s â Ï+ÎœÏ via Ï+ â Ï+Ï0ÂŻÎœÏ
(2021)
By analyzing 6.32 fb â 1 of e+ eâ annihilation data collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we determine the branching fraction of the leptonic decay D + s â Ï + ÎœÏ, with Ï+ â Ï + Ï0ÂŻÎœÏ, to be B D + s â Ï + Îœ Ï = (5.29 ± 0.25 stat ± 0.20 syst) %. We estimate the product of the Cabibbo-Kobayashi-Maskawa matrix element |Vcs|and the D + s decay constant f D + s to be f D + s|Vcs| = (244.8 ± 5.8 stat ± 4.8syst) MeV, using the known values of the Ï + and D + s masses as well as the D + s lifetime, together with our branching fraction measurement. Combining the value of |Vcs| obtained from a global fit in the standard model and f D + s from lattice quantum chromodynamics, we obtain f D + s = (251.6 ± 5.9 stat ± 4.9syst) MeV and |Vcs| = 0.980 ± 0.023 stat ± 0.019 syst. Using the branching fraction of B D + s â ÎŒ + ΜΌ = (5.35±0.21)Ă10â3, we obtain the ratio of the branching fractions B D + s â Ï + ÎœÏ/B D +s â ÎŒ+ΜΌ = 9.89±0.71, which is consistent with the standard model prediction of lepton flavor universality.
Using 10.1 Ă 109 J/Ï events produced by the Beijing Electron Positron Collider (BEPCII) at a center-of-mass energy âs = 3.097 GeV and collected with the BESIII detector, we present a search for the rare semi-leptonic decay J/Ï â Dâe+Îœe + c.c. No excess of signal above background is observed, and an upper limit on the branching fraction âŹ(J/ÏâââDâe+Îœeâ+âc. c.)â<â7.1âĂâ10â8 is obtained at 90% confidence level. This is an improvement of more than two orders of magnitude over the previous best limit.
We measure the inclusive semielectronic decay branching fraction of the D+s meson. A double-tag technique is applied to e+eâ annihilation data collected by the BESIII experiment at the BEPCII collider, operating in the center-of-mass energy range 4.178â4.230 GeV. We select positrons fromD+sâXe+Îœe with momenta greater than 200 MeV/c and determine the laboratory momentum spectrum, accounting for the effects of detector efficiency and resolution. The total positron yield and semielectronic branching fraction are determined by extrapolating this spectrum below the momentum cutoff. We measure the D+s semielectronic branching fraction to be(6.30±0.13(stat.)±0.09(syst.)±0.04(ext.))%, showing no evidence for unobserved exclusive semielectronic modes. We combine this result with external data taken from literature to determine the ratio of the D+s and D0 semielectronic widths, Î(D+sâXe+Îœe)Î(D0âXe+Îœe)=0.790±0.016(stat.)±0.011(syst.)±0.016(ext.). Our results are consistent with and more precise than previous measurements.
Though immensely successful, the standard model of particle physics does not offer any explanation as to why our Universe contains so much more matter than antimatter. A key to a dynamically generated matterâantimatter asymmetry is the existence of processes that violate the combined charge conjugation and parity (CP) symmetry1. As such, precision tests of CP symmetry may be used to search for physics beyond the standard model. However, hadrons decay through an interplay of strong and weak processes, quantified in terms of relative phases between the amplitudes. Although previous experiments constructed CP observables that depend on both strong and weak phases, we present an approach where sequential two-body decays of entangled multi-strange baryonâantibaryon pairs provide a separation between these phases. Our method, exploiting spin entanglement between the double-strange Îâ baryon and its antiparticle2 ÎÂŻ+
, has enabled a direct determination of the weak-phase difference, (ΟPâââΟS)â= (1.2â±â3.4â±â0.8)âĂâ10â2ârad. Furthermore, three independent CP observables can be constructed from our measured parameters. The precision in the estimated parameters for a given data sample size is several orders of magnitude greater than achieved with previous methods3. Finally, we provide an independent measurement of the recently debated Î decay parameter αΠ(refs.â4,5). The ÎÎÂŻ
asymmetry is in agreement with and compatible in precision to the most precise previous measurement.
Based on an e+eâ collision data sample corresponding to an integrated luminosity of 2.93 fbâ1 collected with the BESIII detector at âs=3.773 GeV, the first amplitude analysis of the singly Cabibbo-suppressed decay D+âK+K0SÏ0 is performed. From the amplitude analysis, the Kâ(892)+K0S component is found to be dominant with a fraction of (57.1±2.6±4.2)%, where the first uncertainty is statistical and the second systematic. In combination with the absolute branching fraction B(D+âK+K0SÏ0) measured by BESIII, we obtain B(D+âKâ(892)+K0S)=(8.69±0.40±0.64±0.51)Ă10â3, where the third uncertainty is due to the branching fraction B(D+âK+K0SÏ0). The precision of this result is significantly improved compared to the previous measurement. This result also differs from most of theoretical predictions by about 4Ï, which may help to improve the understanding of the dynamics behind.
Using 448.1 Ă 106 Ï(3686) decays collected with the BESIII detector at the BEPCII e+eâ storage rings, the branching fractions and angular distributions of the decays ÏcJ â ÎâÎÂŻÂŻÂŻÂŻ+ and Î0ÎÂŻÂŻÂŻÂŻ0 (J = 0, 1, 2) are measured based on a partial-reconstruction technique. The decays Ïc1 â Î0ÎÂŻÂŻÂŻÂŻ0 and Ïc2 â Î0ÎÂŻÂŻÂŻÂŻ0 are observed for the first time with statistical significances of 7Ï and 15Ï, respectively. The results of this analysis are in good agreement with previous measurements and have significantly improved precision.
Major mood disorders, which primarily include bipolar disorder and major depressive disorder, are the leading cause of disability worldwide and pose a major challenge in identifying robust risk genes. Here, we present data from independent large-scale clinical data sets (including 29â557 cases and 32â056 controls) revealing brain expressed protocadherin 17 (PCDH17) as a susceptibility gene for major mood disorders. Single-nucleotide polymorphisms (SNPs) spanning the PCDH17 region are significantly associated with major mood disorders; subjects carrying the risk allele showed impaired cognitive abilities, increased vulnerable personality features, decreased amygdala volume and altered amygdala function as compared with non-carriers. The risk allele predicted higher transcriptional levels of PCDH17 mRNA in postmortem brain samples, which is consistent with increased gene expression in patients with bipolar disorder compared with healthy subjects. Further, overexpression of PCDH17 in primary cortical neurons revealed significantly decreased spine density and abnormal dendritic morphology compared with control groups, which again is consistent with the clinical observations of reduced numbers of dendritic spines in the brains of patients with major mood disorders. Given that synaptic spines are dynamic structures which regulate neuronal plasticity and have crucial roles in myriad brain functions, this study reveals a potential underlying biological mechanism of a novel risk gene for major mood disorders involved in synaptic function and related intermediate phenotypes.
Nuclear magnetic resonance (NMR) spectroscopy is a powerful and popular technique for probing the molecular structures, dynamics and chemical properties. However the conventional NMR spectroscopy is bottlenecked by its low sensitivity. Dynamic nuclear polarization (DNP) boosts NMR sensitivity by orders of magnitude and resolves this limitation. In liquid-state this revolutionizing technique has been restricted to a few specific non-biological model molecules in organic solvents. Here we show that the carbon polarization in small biological molecules, including carbohydrates and amino acids, can be enhanced sizably by in situ Overhauser DNP (ODNP) in water at room temperature and at high magnetic field. An observed connection between ODNP 13C enhancement factor and paramagnetic 13C NMR shift has led to the exploration of biologically relevant heterocyclic compound indole. The QM/MM MD simulation underscores the dynamics of intermolecular hydrogen bonds as the driving force for the scalar ODNP in a long-living radical-substrate complex. Our work reconciles results obtained by DNP spectroscopy, paramagnetic NMR and computational chemistry and provides new mechanistic insights into the high-field scalar ODNP.
Gastric cancer is one of the most common malignancies and a leading cause of cancer death worldwide. The prognosis of stomach cancer is generally poor as this cancer is not very sensitive to commonly used chemotherapies. Epigenetic modifications play a key role in gastric cancer and contribute to the development and progression of this malignancy. In order to explore new treatment options in this target area we have screened a library of epigenetic inhibitors against gastric cancer cell lines and identified inhibitors for the BET family of bromodomains as potent inhibitors of gastric cancer cell proliferations. Here we show that both the pan-BET inhibitor (+)-JQ1 as well as a newly developed specific isoxazole inhibitor, PNZ5, showed potent inhibition of gastric cancer cell growth. Intriguingly, we found differences in the antiproliferative response between gastric cancer cells tested derived from Brazilian patients as compared to those from Asian patients, the latter being largely resistant to BET inhibition. As BET inhibitors are entering clinical trials these findings provide the first starting point for future therapies targeting gastric cancer.
A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at sNNââââ=2.76 TeV is reported. Jets are reconstructed from charged particles using the anti-kT jet algorithm with jet resolution parameters R of 0.2 and 0.3 in pseudo-rapidity |η|<0.5. The transverse momentum pT of charged particles is measured down to 0.15 GeV/c which gives access to the low pT fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter R=0.3 considered in the analysis. The fragmentation bias introduced by selecting jets with a high pT leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with R=0.2 and R=0.3 is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with R<0.3.
We study whether prices of traded options contain information about future extreme market events. Our option-implied conditional expectation of market loss due to tail events, or tail loss measure, predicts future market returns, magnitude, and probability of the market crashes, beyond and above other option-implied variables. Stock-specific tail loss measure predicts individual expected returns and magnitude of realized stock-specific crashes in the cross-section of stocks. An investor that cares about the left tail of her wealth distribution benefits from using the tail loss measure as an information variable to construct managed portfolios of a risk-free asset and market index.
Option-implied information and predictability of extreme returns : [Version 24 September 2012]
(2012)
We study whether option-implied conditional expectation of market loss due to tail events, or tail loss measure, contains information about future returns, especially the negative ones. Our tail loss measure predicts future market returns, magnitude, and probability of the market crashes, beyond and above other option-implied variables. Stock-specific tail loss measure predicts individual expected returns and magnitude of realized stock-specific crashes in the cross-section of stocks. An investor, especially the one who cares about the left tail of her wealth distribution (e.g., disappointment-averse), benefits from using the tail loss measure as an information variable to construct managed portfolios of a risk-free asset and market index. The tail loss measure is motivated by the results of the extreme value theory, and it is computed from observed prices of out-of-the-money put as the risk-neutral expected value of a loss beyond a given relative threshold.
Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in pâPb collisions at a nucleonânucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 < pT,assoc < pT,trig < 5.0 GeV/c is examined, to include correlations induced by jets originating from low momentum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range |η| < 0.9. The near-side long-range pseudorapidity correlations observed in high-multiplicity pâPb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple partonâparton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity pâPb collisions. Further, the number scales only in the intermediate multiplicity region with the number of binary nucleonânucleon collisions estimated with a Glauber Monte-Carlo simulation.
We provide the first comprehensive taxonomic revision of the poorly known South American butterfly genus Zischkaia Forster, 1964, hitherto regarded as including three described species. A phylogenetic analysis based on DNA sequence data shows that Zischkaia is monophyletic and consists of two morphologically diagnosable clades. Morphological characters and DNA 'barcodes' support the recognition of twelve species in the genus, a significant increase even for the relatively poorly studied subtribe Euptychiina. Consequently, nine new species are described and named herein, including Z. arctoa Nakahara, sp. nov., Z. chullachaki Nakahara & Zacca, sp. nov., Z. baku Zacca, Dolibaina & Dias, sp. nov., Z. arenisca Nakahara, Willmott & Hall, sp. nov., Z. argyrosflecha Nakahara, L. Miller & Huertas, sp. nov., Z. abanico Nakahara & Petit, sp. nov., Z. josti Nakahara & Kleckner, sp. nov., Z. mielkeorum Dolibaina, Dias & Zacca, sp. nov. and Z. warreni Dias, Zacca & Dolibaina, sp. nov. In addition, a neotype is designated for Satyrus pacarus Godart, [1824], and lectotypes are designated for Euptychia amalda Weymer, 1911, Euptychia fumata Butler, 1867 and Euptychia saundersii Butler, 1867.
On eight species of the spider genus Synagelides Strand, 1906 from China (Araneae: Salticidae)
(2020)
Six new species of Synagelides Strand, 1906 are diagnosed and described: S. bohdanowiczi sp. nov. (ââ), S. leigongensis sp. nov. (ââ), S. logunovi sp. nov. (ââ), S. subgambosus sp. nov. (ââ), S. wuliangensis sp. nov. (ââ) and S. xingdouensis sp. nov. (ââ). The female of S. forkiforma Yang, Zhu & Song, 2007 and the male of S. longus Song & Chai, 1992 are described for the first time. Photos of the habitus and copulatory organs, as well as a distributional map, are provided.
Data is considered the new oil of the economy, but privacy concerns limit their use, leading to a widespread sense that data analytics and privacy are contradictory. Yet such a view is too narrow, because firms can implement a wide range of methods that satisfy different degrees of privacy and still enable them to leverage varied data analytics methods. Therefore, the current study specifies different functions related to data analytics and privacy (i.e., data collection, storage, verification, analytics, and dissemination of insights), compares how these functions might be performed at different levels (consumer, intermediary, and firm), outlines how well different analytics methods address consumer privacy, and draws several conclusions, along with future research directions.
The genus Parandes Muir, 1925 (Cixiinae, Andini) is recorded from China for the first time with two new species, Parandes circinatus Wang & Chen sp. nov. and Parandes fuscus Wang & Chen sp. nov. Color images for the adults of the two new species and line drawings for the genitalia are provided. A key is presented to separate all species within the genus.
In the past two decades, pions created in the high density regions of heavy ion collisions have been predicted to be sensitive at high densities to the symmetry energy term in the nuclear equation of state, a property that is key to our understanding of neutron stars. In a new experiment designed to study the symmetry energy, the multiplicities of negatively and positively charged pions have been measured with high accuracy for central 132Sn+124Sn, 112Sn+124Sn, and 108Sn+112Sn collisions at E/A = 270 MeV with the SÏRIT Time Projection Chamber. While individual pion multiplicities are measured to 4% accuracy, those of the charged pion multiplicity ratios are measured to 2% accuracy. We compare these data to predictions from seven major transport models. The calculations reproduce qualitatively the dependence of the multiplicities and their ratios on the total neutron and proton number in the colliding systems. However, the predictions of the transport models from different codes differ too much to allow extraction of reliable constraints on the symmetry energy from the data. This finding may explain previous contradictory conclusions on symmetry energy constraints obtained from pion data in Au+Au system. These new results call for still better understanding of the differences among transport codes, and new observables that are more sensitive to the density dependence of the symmetry energy.
Coprophagy and probable saprophagy are reported for larvae of two species of chrysaugine moths (Lepidoptera: Pyralidae). Larvae of Parachma ochracealis Walker are found in rotten pine wood and mulch in North-Central Florida. Larvae of Basacallis tarachodes (Dyar) inhabit feces of an unidentified small mammal in a cave in Central Florida and seem to be troglophilic. These behaviors are compared to similar ones in Neotropical chrysaugines such as Humiphila Becker and Cryptoses Dyar. Saprophagy and coprophagy are predicted to be more general habits among Chrysauginae.
This paper provides new geochemical data focusing on valuable elements in the coal, parting, and floor samples in the No. 5 coal seam of the Taiyuan Formation from the Wujiawan mine, Datong coalfield, northern China. The minerals mainly consist of kaolinite, calcite, and pyrite, as well as trace amounts of quartz and illite. The No. 5 coal is enriched in Li, Ga, high field strength elements (HFSEs), and rare earth elements and yttrium (REY) when compared with world hard coals. Of particular interest is the high average concentration of Li (67.66 ÎŒg/g), which is around seven times higher than the value for world hard coals. Lithium, Ga, and HFSEs have strong inorganic affinities, whereas REY have organic affinities. The main carrier of Li, Ga, and HFSEs is aluminosilicate minerals, while REY appear to occur with organophosphorus. These HFSEs are enriched, both in the parting and in the adjacent coal samples. This suggests that these elements are likely to leach out during the diagenetic process. The distribution patterns of REY, along with the ratio of Al2O3/TiO2 and the figure of Zr/TiO2 vs. Nb/Y are suggestive of their derivation from felsic parent material. In the northern and eastern part of the Datong coalfield, there are several regions where the Li content is higher than the mineable grade, in particular in the northern Datong coalfield where there is a mine with an Li content of 294.6 ÎŒg/g. This is significantly higher than the mineable grade. Therefore, there is a potential for financially viable recovery of Li in these coals of the Datong coalfield.
Fourteen species of the subgenus Sinotipula (Diptera, Tipulidae) were previously known to occur in China. Here four species are described and illustrated as new to science: Tipula (Sinotipula) drolma sp. nov., T. (S.) forcipicauda sp. nov., T. (S.) heminga sp. nov. and T. (S.) longiloba sp. nov. The following three species are redescribed: T. (S.) exquisita Alexander, 1935, T. (S.) hobsoni Edwards, 1928 and T. (S.) wardi Edwards, 1928, and a key to the species of Tipula (Sinotipula) from China is presented. We also give a new replacement name for Tipula (Vestiplex) bucera Yang, Li, Pan, Liu & Yang, 2021, i.e., T. (V.) curvicornis nom. nov.
Five new species of the genus Andes StÄl, 1866 from China (Hemiptera, Fulgoromorpha, Cixiidae)
(2022)
Five new species of the genus Andes StÄl, 1866, A. balteiformis Wang, Zhi & Chen sp. nov., A. bifidus Wang, Zhi & Chen sp. nov., A. furcutus Wang, Zhang & Chen sp. nov., A. latanalus Wang & Chen sp. nov. and A. pallidus Wang & Chen sp. nov. from China, are described and illustrated. A key to the species of Andes in China is provided.
Two new species, Russula pseudopunicea C.L.Hou, G.Q.Cheng & H.Zhou sp. nov. and R. wulingshanensis C.L.Hou, G.Q.Cheng & H.Zhou sp. nov., from Yanshan mountains in North China are described herein based on morphological and phylogenetic analyses of nrITS, and nrLSU-rpb2-mtSSU gene regions. Morphologically, R. pseudopunicea sp. nov. is characterised by a reddish brown, light brown to brownish orange pileus with a greyish yellow margin, subglobose to broadly ellipsoid basidiospores with warts forming a partial reticulum and pleurocystidia turning grey to purplish red in sulfovanillin. Russula wulingshanensis sp. nov. is characterised by a purple pinkish pileus with a grey-white to grey-purple margin, subglobose to broadly ellipsoid basidiospores with isolated warts, and pileocystidia turning black in sulfovanillin. Phylogenetic and morphological analyses resolved the two species in Russula subg. Heterophyllidia. Russula pseudopunicea sp. nov. and R. wulingshanensis sp. nov. were placed in the lineages of subsect. Virescentinae and subsect. Griseinae, respectively.
Twelve species of the subgenus Vestiplex (Diptera, Tipulidae) were previously known to occur in Tibet (= Xizang), China. Here, six species are described and illustrated as new to science: Tipula (Vestiplex) bucera sp. nov., Tipula (Vestiplex) magatama sp. nov., Tipula (Vestiplex) motuoensis sp. nov., Tipula (Vestiplex) nayogabuensis sp. nov., Tipula (Vestiplex) platyphylla sp. nov. and Tipula (Vestiplex) uncinella sp. nov. The following three species are redescribed: Tipula (Vestiplex) himalayensis Brunetti, 1911, Tipula (Vestiplex) nigroapicalis Brunetti, 1911 and Tipula (Vestiplex) zayulensis Alexander, 1963. A key to the species of Tipula (Vestiplex) from Tibet is presented.
Freeze-out radii extracted from three-pion cumulants in pp, pâPb and PbâPb collisions at the LHC
(2014)
In high-energy collisions, the spatio-temporal size of the particle production region can be measured using the BoseâEinstein correlations of identical bosons at low relative momentum. The source radii are typically extracted using two-pion correlations, and characterize the system at the last stage of interaction, called kinetic freeze-out. In low-multiplicity collisions, unlike in high-multiplicity collisions, two-pion correlations are substantially altered by background correlations, e.g. mini-jets. Such correlations can be suppressed using three-pion cumulant correlations. We present the first measurements of the size of the system at freeze-out extracted from three-pion cumulant correlations in pp, pâPb and PbâPb collisions at the LHC with ALICE. At similar multiplicity, the invariant radii extracted in pâPb collisions are found to be 5â15% larger than those in pp, while those in PbâPb are 35â55% larger than those in pâPb. Our measurements disfavor models which incorporate substantially stronger collective expansion in pâPb as compared to pp collisions at similar multiplicity.
We report on the measurement of the inclusive ΄ (1S) production in PbâPb collisions at âsNN = 2.76 TeV carried out at forward rapidity (2.5 < y < 4) and down to zero transverse momentum using its ÎŒ+ÎŒâdecay channel with the ALICE detector at the Large Hadron Collider. A strong suppression of the inclusive ΄ (1S) yield is observed with respect to pp collisions scaled by the number of independent nucleonânucleon collisions. The nuclear modification factor, for events in the 0â90% centrality range, amounts to 0.30 ± 0.05(stat) ± 0.04(syst). The observed ΄ (1S) suppression tends to increase with the centrality of the collision and seems more pronounced than in corresponding mid-rapidity measurements. Our results are compared with model calculations, which are found to underestimate the measured suppression and fail to reproduce its rapidity dependence.
J/Ï suppression has long been considered a sensitive signature of the formation of the Quark-Gluon Plasma (QGP) in relativistic heavy-ion collisions. In this letter, we present the first measurement of inclusive J/Ï production at mid-rapidity through the dimuon decay channel in Au+Au collisions at âsNN = 200 GeV with the STAR experiment. These measurements became possible after the installation of the Muon Telescope Detector was completed in 2014. The J/Ï yields are measured in a wide transverse momentum (pT) range of 0.15 GeV/c to 12 GeV/c from central to peripheral collisions. They extend the kinematic reach of previous measurements at RHIC with improved precision. In the 0-10% most central collisions, the J/Ï yield is suppressed by a factor of approximately 3 for pT > 5 GeV/c relative to that in p + p collisions scaled by the number of binary nucleon-nucleon collisions. The J/Ï nuclear modification factor displays little dependence on pT in all centrality bins. Model calculations can qualitatively describe the data, providing further evidence for the color-screening effect experienced by J/Ï mesons in the QGP.
The transverse momentum (pT) spectrum and nuclear modification factor (RAA) of reconstructed jets in 0â10% and 10â30% central PbâPb collisions at âsNN = 2.76 TeV were measured. Jets were reconstructed using the anti-kT jet algorithm with a resolution parameter of R = 0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pT spectra are reported in the pseudorapidity interval of |ηjet| < 0.5 for 40 < pT, jet < 120 GeV/c in 0â10% and for 30 < pT, jet < 100 GeV/c in 10â30% collisions. Reconstructed jets were required to contain a leading charged particle with pT > 5 GeV/c to suppress jets constructed from the combinatorial background in PbâPb collisions. The leading charged particle requirement applied to jet spectra both in pp and PbâPb collisions had a negligible effect on the RAA. The nuclear modification factor RAA was found to be 0.28 ± 0.04 in 0â10% and 0.35 ± 0.04 in 10â30% collisions, independent of pT, jet within the uncertainties of the measurement. The observed suppression is in fair agreement with expectations from two model calculations with different approaches to jet quenching.
New measurements of directed flow for charged hadrons, characterized by the Fourier coefficient v1, are presented for transverse momenta pT, and centrality intervals in Au+Au collisions recorded by the STAR experiment for the center-of-mass energy range âsN N = 7.7â200 GeV. The measurements underscore the importance of momentum conservation, and the characteristic dependencies on âsN N , centrality and pT are consistent with the expectations of geometric fluctuations generated in the initial stages of the collision, acting in concert with a hydrodynamic-like expansion. The centrality and pT dependencies of veven 1 , as well as an observed similarity between its excitation function and that for v3, could serve as constraints for initial-state models. The veven 1 excitation function could also provide an important supplement to the flow measurements employed for precision extraction of the temperature dependence of the specific shear viscosity.
We have performed the first measurement of the coherent Ï(2S) photo production cross section in ultraperipheral PbâPb collisions at the LHC. This charmonium excited state is reconstructed via the Ï(2S) â l +l â and Ï(2S) â J/ÏÏ+Ïâ decays, where the J/Ï decays into two leptons. The analysis is based on an event sample corresponding to an integrated luminosity of about 22 ÎŒbâ1. The cross section for coherent Ï(2S) production in the rapidity interval â0.9 < y < 0.9 is dÏcoh Ï(2S)/dy = 0.83±0.19 stat+syst mb. The Ï(2S) to J/Ï coherent cross section ratio is 0.34+0.08 â0.07(stat + syst). The obtained results are compared to predictions from theoretical models.
Measurement of electrons from heavy-flavour hadron decays in pâPb collisions at âsNN = 5.02 TeV
(2015)
The production of electrons from heavy-flavour hadron decays was measured as a function of transverse momentum (pT) in minimum-bias pâPb collisions at âsNN = 5.02 TeV using the ALICE detector at the LHC. The measurement covers the pT interval 0.5 < pT < 12 GeV/c and the rapidity range â1.065 < ycms < 0.135 in the centre-of-mass reference frame. The contribution of electrons from background sources was subtracted using an invariant mass approach. The nuclear modification factor RpPb was calculated by comparing the pT-differential invariant cross section in pâPb collisions to a pp reference at the same centre-of-mass energy, which was obtained by interpolating measurements at âs = 2.76 TeV and âs = 7 TeV. The RpPb is consistent with unity within uncertainties of about 25%, which become larger for pT below 1 GeV/c. The measurement shows that heavy-flavour production is consistent with binary scaling, so that a suppression in the high-pT yield in PbâPb collisions has to be attributed to effects induced by the hot medium produced in the final state. The data in pâPb collisions are described by recent model calculations that include cold nuclear matter effects.
A measurement of dijet correlations in pâPb collisions at âsNN = 5.02 TeV with the ALICE detector is presented. Jets are reconstructed from charged particles measured in the central tracking detectors and neutral energy deposited in the electromagnetic calorimeter. The transverse momentum of the full jet (clustered from charged and neutral constituents) and charged jet (clustered from charged particles only) is corrected event-by-event for the contribution of the underlying event, while corrections for underlying event fluctuations and finite detector resolution are applied on an inclusive basis. A projection of the dijet transverse momentum, kTy = pch+ne T,jet sin(Ïdijet) with Ïdijet the azimuthal angle between a full and charged jet and pch+ne T,jet the transverse momentum of the full jet, is used to study nuclear matter effects in pâPb collisions. This observable is sensitive to the acoplanarity of dijet production and its potential modification in pâPb collisions with respect to pp collisions. Measurements of the dijet kTy as a function of the transverse momentum of the full and recoil charged jet, and the event multiplicity are presented. No significant modification of kTy due to nuclear matter effects in pâPb collisions with respect to the event multiplicity or a PYTHIA8 reference is observed.
Background: Pancreatic ductal adenocarcinoma remains one of the most lethal malignancies, with few treatment options. NAPOLI 3 aimed to compare the efficacy and safety of NALIRIFOX versus nab-paclitaxel and gemcitabine as first-line therapy for metastatic pancreatic ductal adenocarcinoma (mPDAC).
Methods: NAPOLI 3 was a randomised, open-label, phase 3 study conducted at 187 community and academic sites in 18 countries worldwide across Europe, North America, South America, Asia, and Australia. Patients with mPDAC and Eastern Cooperative Oncology Group performance status score 0 or 1 were randomly assigned (1:1) to receive NALIRIFOX (liposomal irinotecan 50 mg/m2, oxaliplatin 60 mg/m2, leucovorin 400 mg/m2, and fluorouracil 2400 mg/m2, administered sequentially as a continuous intravenous infusion over 46 h) on days 1 and 15 of a 28-day cycle or nab-paclitaxel 125 mg/m2 and gemcitabine 1000 mg/m2, administered intravenously, on days 1, 8, and 15 of a 28-day cycle. Balanced block randomisation was stratified by geographical region, performance status, and liver metastases, managed through an interactive web response system. The primary endpoint was overall survival in the intention-to-treat population, evaluated when at least 543 events were observed across the two treatment groups. Safety was evaluated in all patients who received at least one dose of study treatment. This completed trial is registered with ClinicalTrials.gov, NCT04083235.
Findings: Between Feb 19, 2020 and Aug 17, 2021, 770 patients were randomly assigned (NALIRIFOX, 383; nab-paclitaxelâgemcitabine, 387; median follow-up 16·1 months [IQR 13·4â19·1]). Median overall survival was 11·1 months (95% CI 10·0â12·1) with NALIRIFOX versus 9·2 months (8·3â10·6) with nab-paclitaxelâgemcitabine (hazard ratio 0·83; 95% CI 0·70â0·99; p=0·036). Grade 3 or higher treatment-emergent adverse events occurred in 322 (87%) of 370 patients receiving NALIRIFOX and 326 (86%) of 379 patients receiving nab-paclitaxelâgemcitabine; treatment-related deaths occurred in six (2%) patients in the NALIRIFOX group and eight (2%) patients in the nab-paclitaxelâgemcitabine group.
Interpretation: Our findings support use of the NALIRIFOX regimen as a possible reference regimen for first-line treatment of mPDAC.
The measurement of the mass differences for systems bound by the strong force has reached a very high precision with protons and anti-protons1,2. The extension of such measurement from (anti-)baryons to (anti-)nuclei allows one to probe any difference in the interactions between nucleons and anti-nucleons encoded in the (anti-)nuclei masses. This force is a remnant of the underlying strong interaction among quarks and gluons and can be described by effective theories3, but cannot yet be directly derived from quantum chromodynamics. Here we report a measurement of the difference between the ratios of the mass and charge of deuterons (d) and anti-deuterons (), and 3He and nuclei carried out with the ALICE (A Large Ion Collider Experiment)4 detector in PbâPb collisions at a centre-of-mass energy per nucleon pair of 2.76âTeV. Our direct measurement of the mass-over-charge differences confirms CPT invariance to an unprecedented precision in the sector of light nuclei5,6. This fundamental symmetry of nature, which exchanges particles with anti-particles, implies that all physics laws are the same under the simultaneous reversal of charge(s) (charge conjugation C), reflection of spatial coordinates (parity transformation P) and time inversion (T).
The ALICE Collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y| < 0.8 and transverse momentum 1 < pT < 10 GeV/c, in pp collisions at âs = 2.76 TeV. Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD predictions agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, Ïbâe = 3.47 ± 0.40(stat) +1.12 â1.33(sys) ± 0.07(norm) ÎŒb, was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) calculations to obtain the total bb production ÂŻ cross section, ÏbbÂŻ = 130 ± 15.1(stat) +42.1 â49.8(sys) +3.4 â3.1(extr) ± 2.5(norm) ± 4.4(BR) ÎŒb.
Transverse momentum spectra of ϱ, K± and p(pÂŻ) up to pT = 20 GeV/c at mid-rapidity in pp, peripheral (60â80%) and central (0â5%) PbâPb collisions at âsNN = 2.76 TeV have been measured using the ALICE detector at the Large Hadron Collider. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at pT â 3 GeV/c in central PbâPb collisions. Below the peak, pT < 3 GeV/c, both ratios are in good agreement with hydrodynamical calculations, suggesting that the peak itself is dominantly the result of radial flow rather than anomalous hadronization processes. For pT > 10 GeV/c particle ratios in pp and PbâPb collisions are in agreement and the nuclear modification factors for ϱ, K± and p(pÂŻ) indicate that, within the systematic and statistical uncertainties, the suppression is the same. This suggests that the chemical composition of leading particles from jets in the medium is similar to that of vacuum jets.
We report on the production of inclusive ΄ (1S) and ΄ (2S) in pâPb collisions at âsNN = 5.02 TeV at the LHC. The measurement is performed with the ALICE detector at backward (â4.46 < ycms < â2.96) and forward (2.03 .< ycms < 3.53) rapidity down to zero transverse momentum. The production cross sections of the ΄ (1S) and ΄ (2S) are presented, as well as the nuclear modification factor and the ratio of the forward to backward yields of ΄ (1S). A suppression of the inclusive ΄ (1S) yield in pâPb collisions with respect to the yield from pp collisions scaled by the number of binary nucleonânucleon collisions is observed at forward rapidity but not at backward rapidity. The results are compared to theoretical model calculations including nuclear shadowing or partonic energy loss effect.
Many species of plants and a few species of animals are believed to have resulted from hybridization of parental species, and the ability of species to occasionally hybridize in captivity and in nature is even more widespread. In the present study, we describe a hybridization experiment conducted in the laboratory between the sexually dimorphic Automeris io (Fabricius), a widespread, variable species ranging from Canada to Costa Rica, and its congener A. louisiana (Ferguson and Brou), a more local, sexually monomorphic species (Lepidoptera: Saturniidae). The A. louisiana populations occur in a highly specialized habitatâthe coastal marshland along the Gulf of Mexico in Louisiana and Texas and is nested inside the broad distribution of A. io, demonstrating strong differences from the latter in its ecology and morphology. No natural hybridization between the two species has been described. While the separate species status of A. io and A. louisiana is supported by morphology and ecology of their populations, we were able to create a hybrid lineage in the laboratory and maintained it for three generations. The hybrids were phenotypically intermediate between the parental species. Under a stricter reading of the biological species concept, such an ability to hybridize would be interpreted by some as a sign of conspecificity. Our experiments once again demonstrate the complexity of âspeciesâ as a concept, which may need major redefinition in the popular interpretation of sciences.
New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)1,2,3,4. However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components. The importance of this mechanism depends on the availability of ammonia, which was previously thought to be efficiently scavenged by cloud droplets during convection. However, surprisingly high concentrations of ammonia and ammonium nitrate have recently been observed in the upper troposphere over the Asian monsoon region5,6. Once particles have formed, co-condensation of ammonia and abundant nitric acid alone is sufficient to drive rapid growth to CCN sizes with only trace sulfate. Moreover, our measurements show that these CCN are also highly efficient ice nucleating particlesâcomparable to desert dust. Our model simulations confirm that ammonia is efficiently convected aloft during the Asian monsoon, driving rapid, multi-acid HNO3âH2SO4âNH3 nucleation in the upper troposphere and producing ice nucleating particles that spread across the mid-latitude Northern Hemisphere.
A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog, but how it occurs in cities is often puzzling. If the growth rates of urban particles are similar to those found in cleaner environments (1â10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below â15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acidâbase stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms.