542 research outputs found

    Comparative Genomic Analysis of Latilactobacillus curvatus and L. sakei

    Get PDF
    In this study, the genomes of 19 Latilactobacillus curvatus and 40 L. sakei strains were comparatively analyzed. Average nucleic acid identity (ANI) and genome-wide colinearity indicated that the genomes of L. curvatus and L. sakei had weak nucleotide sequence homology, allowing them to be used as indicators to distinguish the two species. Pangenomes for these species were constructed, whose core gene functions were annotated. The results showed that the core genomes of L. curvatus and L. sakei were mainly involved in their basic metabolism. Analysis of individual genomes of the strains revealed that 1) both L. curvatus and L. sakei contained a wide range of genes encoding glycoside hydrolases, which are abundant genetic resources for catabolizing and metabolizing dietary fiber such as polysaccharides, lactose utilization, and lignocellulose; 2) antibiotic resistance genes were annotated in the genomes of three strains, which originate from horizontal gene transfer; 3) the unique arginine deiminase pathway of L. sakei, the serine dehydratase and guanine deaminase pathways of L. curvatus, and the glutamate decarboxylase pathway of several strains were identified, revealing that the acid tolerance mechanisms of these two species are different; and 4) genes encoding cold stress proteins were discovered, which endow the two species with good cold processing properties. Moreover, the genomes of some L. sakei strains contained gene clusters related to the biosynthesis of lactocin S and condensin. In conclusion, this study established taxonomic criteria for the two species and information on individual differences between their strains, which will provide a basis for the study of the physiological, biochemical, molecular genetic mechanisms of L. curvatus and L. sakei and their industrial applications

    Intraocular pressure effect of intravitreal conbercept injection for retinopathy of prematurity

    Get PDF
    Purpose: Intravitreal injection of conbercept (IVC) is a novel anti-vascular endothelial growth factor (anti-VEGF) treatment for retinopathy of prematurity (ROP). This study aimed to assess the intraocular pressure (IOP) effect of IVC.Methods: All IVC surgeries were performed in the Department of Ophthalmology, Guangdong Women and Children Hospital, from January 2021 to May 2021. In this study, 30 eyes of 15 infants who received intravitreal injections of conbercept at a dose of 0.25 mg/0.025 mL were included. The IOP of all participants was measured prior to administering the injection and subsequently at 2 min, 1 h, 1 day, and 1 week thereafter.Results: We included 30 eyes (10 boys and 5 girls) with ROP. For the male group, the mean birth weight, mean gestational age at birth, and the mean time of postmenstrual age (PMA) at IVC treatment were 1,174.0 ± 446.0 g, 28.4 ± 3.0 weeks, and 37.1 ± 1.6 weeks, respectively; for the female group, they were 1,108 ± 285.5 g, 28.2 ± 2.5 weeks, and 36.8 ± 2.1 weeks, respectively. For the male group, the IOP at baseline, 2 min, 1 h, 1 day, and 1 week after IVC were 12.4 ± 1.5 mmHg, 49.0 ± 3.1 mmHg, 26.3 ± 2.5 mmHg, 13.4 ± 2.2 mmHg, and 11.6 ± 1.7 mmHg, respectively; for the female group, they were 10.7 ± 2.0 mmHg, 47.3 ± 3.2 mmHg, 26.4 ± 3.2 mmHg, 10.7 ± 1.8 mmHg, and 10.2 ± 1.8 mmHg, respectively. In both groups, the IOP immediately (2 min) after the operation was significantly higher than that at any other time point (p < 0.01). IOP values returned to the preoperative baseline level on the first day after surgery, with no significant difference compared with that before injection (p > 0.05). IOP continued to be maintained at the preoperative baseline level on the first week after surgery, with no significant difference compared with that before surgery (p > 0.05).Conclusion: Infants with ROP who received IVC experienced a sharp increase in the IOP immediately after injection, which decreased to below 30 mmHg after 1 h and maintain that level for 1 week or longer

    Study of the doubly Cabibbo-suppressed decays Ds+K+K+πD^+_s\to K^+K^+\pi^- and Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0

    Full text link
    Based on 7.33 fb1^{-1} of e+ee^+e^- collision data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, the experimental studies of the doubly Cabibbo-suppressed decays Ds+K+K+πD^+_s\to K^+K^+\pi^- and Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0 are reported. We determine the absolute branching fraction of Ds+K+K+πD^+_s\to K^+K^+\pi^- to be (1.230.25+0.28(stat)±0.06(syst){1.23^{+0.28}_{-0.25}}({\rm stat})\pm0.06({\rm syst})) ×104\times 10^{-4}. No significant signal of Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0 is observed and the upper limit on its decay branching fraction at 90\% confidence level is set to be 1.7×1041.7\times10^{-4}.Comment: 10 pages, 4 figures, 4 table

    Updated measurements of the M1 transition ψ(3686)γηc(2S)\psi(3686) \to \gamma \eta_{c}(2S) with ηc(2S)KKˉπ\eta_{c}(2S) \to K \bar{K} \pi

    Full text link
    Based on a data sample of (27.08±0.14)×108 ψ(3686)(27.08 \pm 0.14 ) \times 10^8~\psi(3686) events collected with the BESIII detector at the BEPCII collider, the M1 transition ψ(3686)γηc(2S)\psi(3686) \to \gamma \eta_{c}(2S) with ηc(2S)KKˉπ\eta_{c}(2S) \to K\bar{K}\pi is studied, where KKˉπK\bar{K}\pi is K+Kπ0K^{+} K^{-} \pi^{0} or KS0K±πK_{S}^{0}K^{\pm}\pi^{\mp}. The mass and width of the ηc(2S)\eta_{c}(2S) are measured to be (3637.8±0.8(stat)±0.2(syst))(3637.8 \pm 0.8 (\rm {stat}) \pm 0.2 (\rm {syst})) MeV/c2c^{2} and (10.5±1.7(stat)±3.5(syst))(10.5 \pm 1.7 (\rm {stat}) \pm 3.5 (\rm {syst})) MeV, respectively. The product branching fraction B(ψ(3686)γηc(2S))×B(ηc(2S)KKˉπ)\mathcal{B}\left(\psi(3686) \rightarrow \gamma \eta_{c}(2 S)\right) \times \mathcal{B}(\eta_{c}(2 S) \rightarrow K \bar{K} \pi) is determined to be (0.97±0.06(stat)±0.09(syst))×105(0.97 \pm 0.06 (\rm {stat}) \pm 0.09 (\rm {syst})) \times 10^{-5}. Using BR(ηc(2S)KKˉπ)=(1.860.49+0.68)%\mathcal{BR}(\eta_{c}(2S)\to K\bar{K}\pi)=(1.86^{+0.68}_{-0.49})\%, we obtain the branching fraction of the radiative transition to be BR(ψ(3686)γηc(2S))=(5.2±0.3(stat)±0.5(syst)1.4+1.9(extr))×104\mathcal{BR}(\psi(3686) \to \gamma \eta_{c}(2S)) = (5.2 \pm 0.3 (\rm {stat}) \pm 0.5 (\rm {syst}) ^{+1.9}_{-1.4} (extr)) \times 10^{-4}, where the third uncertainty is due to the quoted BR(ηc(2S)KKˉπ)\mathcal{BR}(\eta_{c}(2S) \to K\bar{K}\pi)

    Search for hidden-charm tetraquark with strangeness in e+eK+DsD0+c.c.e^{+}e^{-}\rightarrow K^+ D_{s}^{*-} D^{*0}+c.c.

    Full text link
    We report a search for a heavier partner of the recently observed Zcs(3985)Z_{cs}(3985)^{-} state, denoted as ZcsZ_{cs}^{\prime -}, in the process e+eK+DsD0+c.c.e^{+} e^{-}\rightarrow K^{+}D_{s}^{*-}D^{* 0}+c.c., based on e+ee^+e^- collision data collected at the center-of-mass energies of s=4.661\sqrt{s}=4.661, 4.682 and 4.699 GeV with the BESIII detector. The ZcsZ_{cs}^{\prime -} is of interest as it is expected to be a candidate for a hidden-charm and open-strange tetraquark. A partial-reconstruction technique is used to isolate K+K^+ recoil-mass spectra, which are probed for a potential contribution from ZcsDsD0Z_{cs}^{\prime -}\to D_{s}^{*-}D^{* 0} (c.c.c.c.). We find an excess of ZcsDsD0Z_{cs}^{\prime -}\rightarrow D_{s}^{*-}D^{*0} (c.c.c.c.) candidates with a significance of 2.9σ2.9\sigma, after considering systematic uncertainties, at a mass of (4123.5±0.7stat.±1.1syst.)MeV/c2(4123.5 \pm 0.7_{\mathrm{stat.}} \pm 1.1_{\mathrm{syst.}}) \mathrm{MeV}/c^{2}. As the data set is limited in size, the upper limits are evaluated at the 90% confidence level on the product of the Born cross section and the branching fraction of ZcsDsD0Z_{cs}^{\prime-}\rightarrow D_{s}^{*-}D^{* 0}, σBornB\sigma^{\rm Born}\cdot\mathcal{B} at the three energy points, under different assumptions of the ZcsZ_{cs}^{\prime -} mass from 4.120 to 4.140 MeV and of the width from 10 to 50 MeV. Under various mass and width assumptions, the upper limits of σBornB\sigma^{\rm Born}\cdot\mathcal{B} are found to lie in the range of 262\sim6, 373\sim7 and 363\sim6 pb at s=4.661\sqrt{s}=4.661, 4.682 and 4.699 GeV, respectively. The larger data samples that will be collected in the coming years will allow a clearer picture to emerge concerning the existence and nature of the ZcsZ_{cs}^{\prime -} state.Comment: 17 pages, 7 figure

    Precise Measurements of Decay Parameters and CPCP Asymmetry with Entangled ΛΛˉ\Lambda-\bar{\Lambda} Pairs

    Full text link
    Based on 10 billion J/ψJ/\psi events collected at the BESIII experiment, a search for CPCP violation in Λ\Lambda decay is performed in the difference between CPCP-odd decay parameters α\alpha_{-} for Λpπ\Lambda \rightarrow p\pi^- and α+\alpha_{+} for Λˉpˉπ+\bar\Lambda \rightarrow \bar{p}\pi^+ by using the process e+eJ/ψΛΛˉe^+e^- \to J/\psi \rightarrow \Lambda \bar\Lambda . With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α=0.7519±0.0036±0.0024\alpha_{-} = 0.7519 \pm 0.0036 \pm 0.0024 and α+=0.7559±0.0036±0.0030\alpha_{+} = -0.7559 \pm 0.0036 \pm 0.0030, respectively. The Λ\Lambda and Λˉ\bar{\Lambda} averaged value of the decay parameter is extracted to be αavg=0.7542±0.0010±0.0024\alpha_{\rm{avg}} = 0.7542 \pm 0.0010 \pm 0.0024 with unprecedented accuracy. The CPCP asymmetry ACP=(α+α+)/(αα+)A_{CP}=(\alpha_{-}+\alpha_{+})/(\alpha_{-}-\alpha_{+}) is determined to be 0.0025±0.0046±0.0012-0.0025 \pm 0.0046 \pm 0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CPCP violations for the strange, charmed and beauty baryons

    Study of η(1405)/η(1475)\eta(1405)/\eta(1475) in J/ψγKS0KS0π0J/\psi\to\gamma K^{0}_{S} K^{0}_{S}\pi^{0} decay

    Full text link
    Using a sample of (10.09±0.04)×109(10.09\pm0.04)\times10^{9} J/ψJ/\psi decays collected with the BESIII detector, partial wave analyses of the decay J/ψγKS0KS0π0J/\psi\to\gamma K^{0}_{S} K^{0}_{S}\pi^{0} are performed within the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass region below 1.6 GeV/c2{\textrm{GeV}/c^2}. The covariant tensor amplitude method is used in both mass independent and mass dependent approaches. Both analysis approaches exhibit dominant pseudoscalar and axial vector components, and show good consistency for the other individual components. Furthermore, the mass dependent analysis reveals that the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass spectrum for the pseudoscalar component can be well described with two isoscalar resonant states, i.e.{\it i.e.}, the η(1405)\eta(1405) with a mass of 1391.7±0.70.3+11.31391.7\pm0.7_{-0.3}^{+11.3} MeV/c2\textrm{MeV}/c^2 and a width of 60.8±1.212.0+5.560.8\pm1.2_{-12.0}^{+5.5} MeV\textrm{MeV}, and the η(1475)\eta(1475) with a mass of 1507.6±1.632.2+15.51507.6\pm1.6_{-32.2}^{+15.5} MeV/c2\textrm{MeV}/c^2 and a width of 115.8±2.410.9+14.8115.8\pm2.4_{-10.9}^{+14.8} MeV\textrm{MeV}. The first and second uncertainties are statistical and systematic, respectively. Alternate models for the pseudoscalar component are also tested, but the description of the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass spectrum deteriorates significantly.Comment: 20 pages, 6 figures, 6 table

    Amplitude analysis and branching fraction measurement of the decay \boldmath Ds+K+π+ππ0D_{s}^{+} \to K^+\pi^{+}\pi^{-}\pi^{0}

    Full text link
    The singly Cabibbo-suppressed decay Ds+K+π+ππ0D_{s}^{+} \to K^+\pi^{+}\pi^{-}\pi^{0} is observed, using a data set corresponding to an integrated luminosity of 6.32 fb1\rm fb^{-1} recorded by the BESIII detector at the centre-of-mass energies between 4.178 and 4.226 GeV. The first amplitude analysis of Ds+K+π+ππ0D_{s}^{+} \to K^+\pi^{+}\pi^{-}\pi^{0} reveals the sub-structures in this decay and determines the fractions and relative phases of different intermediate processes. The dominant intermediate process is Ds+K0ρ+D_s^+ \to K^{*0}\rho^+, with a fit fraction of (40.5±2.8stat.±1.5syst.)%(40.5\pm2.8_{\rm{stat.}}\pm1.5_{\rm{syst.}})\%. With the detection efficiency based on our amplitude analysis, the absolute branching fraction for Ds+K+π+ππ0D_{s}^{+} \to K^+\pi^{+}\pi^{-}\pi^{0} is measured to be (9.75±0.54stat.±0.17syst.)×103(9.75\pm0.54_{\rm{stat.}}\pm0.17_{\rm{syst.}})\times 10^{-3}

    Observation of the Y(4230)Y(4230) and evidence for a new vector charmonium-like state Y(4710)Y(4710) in e+eKS0KS0J/ψe^{+}e^{-}\to K_{S}^{0} K_{S}^{0} J/\psi

    Full text link
    Cross sections for the process e+eKS0KS0J/ψe^{+} e^{-} \to K_{S}^{0} K_{S}^{0} J/\psi at center-of-mass energies from 4.1284.128 to 4.9504.950 GeV are measured using data samples with a total integrated luminosity of 21.2 fb1^{-1} collected by the BESIII detector operating at the BEPCII storage ring. The Y(4230)Y(4230) state is observed in the energy dependence of the e+eKS0KS0J/ψe^{+} e^{-} \to K_{S}^{0} K_{S}^{0} J/\psi cross section for the first time with a statistical significance of 26.0σ\sigma. In addition, an enhancement around 4.7104.710 GeV, called the Y(4710)Y(4710), is seen with a statistical significance of 4.2σ\sigma. There is no clear structure around 4.4844.484 GeV. Using a fit with a coherent sum of three Breit-Wigner functions, we determine the mass and width of the Y(4230)Y(4230) state to be 4226.9±6.6±21.94226.9 \pm 6.6 \pm 21.9 MeV/c2c^{2} and 71.7±16.2±31.471.7 \pm 16.2 \pm 31.4 MeV, respectively, and the mass and width of the Y(4710)Y(4710) state to be 4704.0±52.3±69.54704.0 \pm 52.3 \pm 69.5 MeV/c2c^{2} and 183.2±114.0±90.8183.2 \pm 114.0 \pm 90.8 MeV, respectively, where the first uncertainties are statistical and the second are systematic. In addition, the average Born cross section ratio of e+eKS0KS0J/ψe^{+} e^{-} \to K_{S}^{0} K_{S}^{0} J/\psi to e+eK+KJ/ψe^{+} e^{-} \to K^{+} K^{-} J/\psi is measured to be 0.3880.028+0.035±0.0160.388_{-0.028}^{+0.035}\pm0.016, or 0.4260.031+0.038±0.0180.426_{-0.031}^{+0.038}\pm0.018 if three-body phase space is considered.Comment: Update draft based the comments from PRD refere
    corecore