The role of virus infection in abdominal aortic aneurysm aetiology

Background. Contemporary studies on aneurysm formation in the course of inflammatory changes led to trials on the role of virus infection in its pathology. Some data in literature indicate infections of the aneurysm wall with such viruses as cytomegalovirus (CMV) and herpes simplex virus type 1, 2 (HSV 1/2). These microorganisms, causing subclinical, chronic or recurrent infections, may have a long-lasting, damaging influence on the aortic wall. The study objective was to solve the following problems: 1. Can the presence of viruses be a factor that causes abdominal aortic aneurysm formation? 2. Does the division of aneurysms into two groups (non-specific and inflammatory) have a clinical nature, or does it result from their different aetiology? Material and methods. Polymerase chain reaction (PCR) tests on DNA presence of CMV, HSV 1/2 and human papilloma virus type 6, 11 (HPV 6/11) were carried out on 34 patients with recognized abdominal aortic aneurysms (AAA), 30 patients with artery atherosclerosis (AA) and at 20 volunteers from a control group. Results. DNA of CMV was detected in none of the tested groups of aortas; HSV 1/2 was detected in one control issue. DNA presence of HPV 6/11 was detected in 100% of tissues taken from aneurysmatic walls, as well as in 14 samples (46.7%) received from atherosclerotic aortas and in 17 tissues (85%) from control aortas. Conclusions. The results suggest that the presence of HPV 6/11 is not a causative factor of AAA. However, the presence of these viruses, even in latent form, may lead to aortic wall weakness and increased susceptibility to secondary infection of C. pneumoniae bacteria, the presence of which was confirmed in previously demonstrated test results.Wstęp. Wyniki współczesnych badań dotyczących powstawania tętniaków w przebiegu zmian zapalnych zapoczątkowały doświadczenia nad znaczeniem zakażeń wirusowych w ich patologii. W piśmiennictwie znajdują się dane, które wskazują na zakażenie ściany tętniaka wirusami, takimi jak cytomegalowirus (CMV) i wirus opryszczki pospolitej typu 1, 2 (HSV). Drobnoustroje te wywołując subkliniczne, przewlekłe lub nawracające zakażenia, mogą wywierać długotrwały uszkadzający wpływ na ścianę aorty. Celem niniejszej pracy było ustalenie: 1. Czy obecność wirusów może być czynnikiem wywołującym powstanie tętniaka aorty brzusznej (AAA)? 2. Czy podział tętniaków na tętniaki niespecyficzne i zapalne ma charakter kliniczny czy też wynika z ich różnej etiologii? Materiał i metody. Badania reakcji łańcuchowej polimerazy (PCR) na obecność DNA CMV, HSV 1/2 i wirusa brodawczaka ludzkiego typu 6, 11 (HPV 6/11) wykonano u 34 osób z rozpoznanym AAA, u 30 chorych z miażdżycą aorty (AA) i u 20 osób z grupy kontrolnej. Wyniki. W żadnej badanej grupie aort nie wykryto występowania DNA CMV, natomiast HSV 1/2 wykryto w jednej tkance kontrolnej. Obecność DNA HPV 6/11 stwierdzono w 100% tkanek pobranych ze ściany tętniaków, jak również w 14 próbach (46,7%) pochodzących z aort zmienionych miażdżycowo i 17 tkankach (85%) aort kontrolnych. Wnioski. Wynik sugeruje, że obecność wirusa HPV 6/11 nie jest czynnikiem sprawczym powstania AAA. Obecność tych wirusów, nawet w formie utajonej, może jednak spowodować osłabienie ściany aorty i zwiększoną podatność na wtórne zakażenie - na przykład bakterią C. pneumoniae, której obecność potwierdzono we wcześniej prezentowanych wynikach badań

Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Measurement of the Λb0→J/ψΛ\Lambda^0_b\rightarrow J/\psi\Lambda angular distribution and the Λb0\Lambda^0_b polarisation in pppp collisions

International audienceThis paper presents an analysis of the ${\Lambda}_b^0$→ J/ψΛ angular distribution and the transverse production polarisation of ${\Lambda}_b^0$ baryons in proton-proton collisions at centre-of-mass energies of 7, 8 and 13 TeV. The measurements are performed using data corresponding to an integrated luminosity of 4.9 fb$^{−1}$, collected with the LHCb experiment. The polarisation is determined in a fiducial region of ${\Lambda}_b^0$ transverse momentum and pseudorapidity of 1 < p$_{T}$< 20 GeV/c and 2 < η < 5, respectively. The data are consistent with ${\Lambda}_b^0$ baryons being produced unpolarised in this region. The parity-violating asymmetry parameter of the Λ → pπ$^{−}$ decay is also determined from the data and its value is found to be consistent with a recent measurement by the BES III collaboration.[graphic not available: see fulltext

Constraints on the KS0→μ+μ−K^0_S \rightarrow \mu^+ \mu^- Branching Fraction

International audienceA search for the decay KS0→μ+μ- is performed using proton-proton collision data, corresponding to an integrated luminosity of 5.6  fb-1 and collected with the LHCb experiment during 2016, 2017, and 2018 at a center-of-mass energy of 13 TeV. The observed signal yield is consistent with zero, yielding an upper limit of B(KS0→μ+μ-)<2.2×10-10 at 90% C.L.. The limit reduces to B(KS0→μ+μ-)<2.1×10-10 at 90% C.L. once combined with the result from data taken in 2011 and 2012

Search for A′→μ+μ−A'\to\mu^+\mu^- Decays

International audienceSearches are performed for both promptlike and long-lived dark photons, A′, produced in proton-proton collisions at a center-of-mass energy of 13 TeV. These searches look for A′→μ+μ- decays using a data sample corresponding to an integrated luminosity of 5.5  fb-1 collected with the LHCb detector. Neither search finds evidence for a signal, and 90% confidence-level exclusion limits are placed on the γ–A′ kinetic mixing strength. The promptlike A′ search explores the mass region from near the dimuon threshold up to 70 GeV and places the most stringent constraints to date on dark photons with 214<m(A′)≲740  MeV and 10.6<m(A′)≲30  GeV. The search for long-lived A′→μ+μ- decays places world-leading constraints on low-mass dark photons with lifetimes O(1)  ps

Measurement of Ξcc++\mathit{\Xi}_{cc}^{++} production in pppp collisions at s=13\sqrt{s}=13 TeV

International audienceThe production of baryons in proton-proton collisions at a centre-of-mass energy of is measured in the transverse-momentum range and the rapidity range . The data used in this measurement correspond to an integrated luminosity of , recorded by the LHCb experiment during 2016. The ratio of the production cross-section times the branching fraction of the decay relative to the prompt production cross-section is found to be , assuming the central value of the measured lifetime, where the first uncertainty is statistical and the second systematic