First Measurement of Λ_{c} Baryon Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of the charmed baryon Λ_{c}^{±} production at midrapidity (|y|<1) in Au+Au collisions at sqrt[s_{NN}]=200  GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The Λ_{c}/D^{0} [denoting (Λ_{c}^{+}+Λ_{c}^{-})/(D^{0}+D[over ¯]^{0})] yield ratio is measured to be 1.08±0.16  (stat)±0.26  (sys) in the 0%-20% most central Au+Au collisions for the transverse momentum (p_{T}) range 3<p_{T}<6  GeV/c. This is significantly larger than the pythia model calculations for p+p collisions. The measured Λ_{c}/D^{0} ratio, as a function of p_{T} and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au+Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured Λ_{c}/D^{0} ratio.

Staged horizontal bone augmentation for dental implants in aesthetic zones: A prospective randomized controlled clinical trial comparing a half-columnar bone block harvested from the ramus versus a rectangular bone block from the symphysis

In this study, the clinical outcomes of horizontal ridge augmentation using half-columnar bone grafts from the ramus (group I: 27 patients, 32 implants) versus rectangular bone grafts from the symphysis (group II: 19 patients, 27 implants) were compared; grafts were combined with organic bovine bone and collagen membrane. Cone beam computed tomography images were obtained preoperatively, immediately after restoration (baseline), and 1 year after loading. Four months after grafting, horizontal bone resorption at the alveolar crest did not differ significantly between the two groups (P=0.291). At 4mm apical to the alveolar crest, horizontal bone resorption in group I was significantly less than that in group II (P=0.041). One year after loading, horizontal bone resorption in group I was lower than that in group II, with no significant difference. The residual thickness of the labial bone at the implant site in group I was significantly higher than that in group II. Horizontal ridge augmentation with either a half-columnar autogenous graft from the ramus or a rectangular autogenous graft from the symphysis can provide acceptable results in aesthetic regions. The half-columnar group demonstrated better graft stability both at 4 months after augmentation and 1 year after loading.

RAI3 knockdown enhances osteogenic differentiation of bone marrow mesenchymal stem cells via STAT3 signaling pathway

Bone marrow mesenchymal stem cells (BMSCs), which have multipotential differentiation and self-renewal ability, have been becoming an attractive source of seed cells for bone tissue engineering. Nonetheless, the precise underlying mechanisms of osteogenesis of BMSCs have not been fully understood. Retinoic acid-induced gene 3 (RAI3) has been found to play important roles in mesenchymal stem cells (MSCs) adipogenesis in our previous study. However, its function in the osteogenic differentiation of BMSCs remains unknown. In this study, we found that RAI3 was significantly reduced in osteogenically differentiated BMSCs; RAI3 knockdown promoted osteogenesis of BMSCs both in vitro and in vivo. Moreover, we found RAI3 knockdown significantly upregulated the expression level of phosphorylated signal transducer and activator of transcription 3 (p-STAT3), and AG-490 which can inhibit the STAT3 signaling reversed the enhancing effect of RAI3 knockdown on the osteogenic differentiation of BMSCs. These results suggest that RAI3 plays important roles in BMSCs osteogenesis with an involvement of the STAT3 signaling, which might open a new avenue to explore BMSCs osteogenesis for the application of BMSCs in bone regeneration.

Measurement of f_{s}/f_{u} Variation with Proton-Proton Collision Energy and B-Meson Kinematics

The ratio of the B_{s}^{0} and B^{+} fragmentation fractions f_{s} and f_{u} is studied with B_{s}^{0}→J/ψϕ and B^{+}→J/ψK^{+} decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8, and 13 TeV center-of-mass energies. The analysis is performed in bins of B-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity, and rapidity. The fragmentation-fraction ratio f_{s}/f_{u} is observed to depend on the B-meson transverse momentum with a significance of 6.0σ. This dependency is driven by the 13 TeV sample (8.7σ), while the results for the other collision energies are not significant when considered separately. Furthermore, the results show a 4.8σ evidence for an increase of f_{s}/f_{u} as a function of collision energy.

Isospin Amplitudes in Λ_{b}^{0}→J/ψΛ(Σ^{0}) and Ξ_{b}^{0}→J/ψΞ^{0}(Λ) Decays

Ratios of isospin amplitudes in hadron decays are a useful probe of the interplay between weak and strong interactions and allow searches for physics beyond the standard model. We present the first results on isospin amplitudes in b-baryon decays, using data corresponding to an integrated luminosity of 8.5  fb^{-1}, collected with the LHCb detector in pp collisions at center of mass energies of 7, 8, and 13 TeV. The isospin amplitude ratio |A_{1}(Λ_{b}^{0}→J/ψΣ^{0})/A_{0}(Λ_{b}^{0}→J/ψΛ)|, where the subscript on A indicates the final-state isospin, is measured to be less than 1/21.8 at 95% confidence level. The Cabibbo suppressed Ξ_{b}^{0}→J/ψΛ decay is observed for the first time, allowing for the measurement |A_{0}(Ξ_{b}^{0}→J/ψΛ)/A_{1/2}(Ξ_{b}^{0}→J/ψΞ^{0})|=0.37±0.06±0.02, where the uncertainties are statistical and systematic, respectively.

The effects of dietary sodium butyrate supplementation on the growth performance, carcass traits and intestinal microbiota of growing-finishing pigs

AIM

This study was carried out to investigate the effects of dietary sodium butyrate supplementation on growth performance, carcass traits and intestinal of growing-finishing pigs.

METHODS AND RESULTS

Thirty pigs (27·4 ± 0·4 kg) were randomly assigned to receive one of three diets: basal diet (negative control group), basal diet + 40 ppm zinc bacitracin (positive control group) and basal diet + 0·2% sodium butyrate (sodium butyrate group), respectively. The experiment lasted for 69 days, including 3 days for diet and housing condition adaptation. On day 70, five piglets from each diet group were slaughtered for collecting blood and tissue samples. When compared to the control group, final body weight, daily body weight gain and daily feed intake of pigs in the sodium butyrate group were increased (P < 0·05) and feed intake/body weight gain ratio was decreased (P < 0·05). Carcass weight of pigs in the sodium butyrate group was higher than that of pigs in the negative and positive groups (P < 0·05); backfat thickness of pigs in the positive group was higher than that of pigs in the negative group and sodium butyrate group (P < 0·001). When compared to the negative and positive groups, pigs fed diet supplemented with sodium butyrate showed a increased relative abundance of bacteroidetes in the caecum and a decreased relative abundance of fiemicutes and proteobacteria in the caecum (P < 0·05).

CONCLUSION

The results indicated that dietary sodium butyrate supplementation increased growth performance of growing-finishing pigs and improved the carcass traits and intestinal health.

SIGNIFICANCE AND IMPACT OF THE STUDY

Antibiotic-free feed has become an inevitable worldwide trend. This study showed that dietary sodium butyrate supplementation improved the growth performance and intestinal health of growing-finishing pigs. Thus, sodium butyrate can be applied in growing-finishing pig feed as an alternative of antibiotics.

First Observation of Excited Ω_{b}^{-} States

We report four narrow peaks in the Ξ_{b}^{0}K^{-} mass spectrum obtained using pp collisions at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1} recorded by the LHCb experiment. Referring to these states by their mass, the mass values are m[Ω_{b}(6316)^{-}]=6315.64±0.31±0.07±0.50  MeV, m[Ω_{b}(6330)^{-}]=6330.30±0.28±0.07±0.50  MeV, m[Ω_{b}(6340)^{-}]=6339.71±0.26±0.05±0.50  MeV, m[Ω_{b}(6350)^{-}]=6349.88±0.35±0.05±0.50  MeV, where the uncertainties are statistical, systematic, and the last is due to the knowledge of the Ξ_{b}^{0} mass. The natural widths of the three lower mass states are consistent with zero, and the 90% confidence-level upper limits are determined to be Γ[Ω_{b}(6316)^{-}]<2.8  MeV, Γ[Ω_{b}(6330)^{-}]<3.1  MeV and Γ[Ω_{b}(6340)^{-}]<1.5  MeV. The natural width of the Ω_{b}(6350)^{-} peak is 1.4_{-0.8}^{+1.0}±0.1  MeV, which is 2.5σ from zero and corresponds to an upper limit of 2.8 MeV. The peaks have local significances ranging from 3.6σ to 7.2σ. After accounting for the look-elsewhere effect, the significances of the Ω_{b}(6316)^{-} and Ω_{b}(6330)^{-} peaks are reduced to 2.1σ and 2.6σ, respectively, while the two higher mass peaks exceed 5σ. The observed peaks are consistent with expectations for excited Ω_{b}^{-} resonances.

Search for A^{'}→μ^{+}μ^{-} Decays

Searches 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.

Observation of Several Sources of CP Violation in B^{+}→π^{+}π^{+}π^{-} Decays

Observations are reported of different sources of CP violation from an amplitude analysis of B^{+}→π^{+}π^{+}π^{-} decays, based on a data sample corresponding to an integrated luminosity of 3  fb^{-1} of pp collisions recorded with the LHCb detector. A large CP asymmetry is observed in the decay amplitude involving the tensor f_{2}(1270) resonance, and in addition significant CP violation is found in the π^{+}π^{-}S wave at low invariant mass. The presence of CP violation related to interference between the π^{+}π^{-}S wave and the P wave B^{+}→ρ(770)^{0}π^{+} amplitude is also established; this causes large local asymmetries but cancels when integrated over the phase space of the decay. The results provide both qualitative and quantitative new insights into CP -violation effects in hadronic B decays.

Three-dimensional cell printing of gingival fibroblast/acellular dermal matrix/gelatin–sodium alginate scaffolds and their biocompatibility evaluation in vitro

3D cell printing of gingival fibroblast/acellular dermal matrix/gelatin–sodium alginate scaffolds showed satisfactory biological properties.

A Multicenter Study of Multimorbidity in Older Adult Inpatients in China

OBJECTIVES

Multimorbidity is common in older hospitalized adults. To date, however, few studies have addressed multimorbidity in the older population of Chinese inpatients. We aimed to investigate the multimorbidity rate and associated risk factors in older adult inpatients in China.

DESIGN, SETTING, PARTICIPANTS

This study was conducted in the medical wards of a tertiary-care hospital from. The patients were recruited aged between 60 to 101 (74.14±8.46) years.

MEASUREMENTS

Data were obtained from the China Comprehensive Geriatric Assessment Study, conducted in 2011-2012 in China. A total of 4,633 inpatients older than 60 years was recruited from 12 hospitals in 7 cities throughout China. The prevalence of comorbidity, distribution of common chronic diseases, and the associated risk factors were studied.

RESULTS

A total of 4,348 people aged 60 to 101 (74.14±8.46) years completed questionnaires. The average frequency of multimorbidity was 69.3% (95% CI, 67.9% to 70.6%). The prevalence of multimorbidity increased with age and was higher in men (71.6%; 95% CI, 69.9% to 73.3%) than in women (65.3%, 95% CI 63.0% to 67.6%), and higher in the northern region (71.7%, 95% CI 69.9% to 73.5%) than in the southern region (66.0%; 95% CI, 63.8% to 68.1%). The most frequent chronic diseases were hypertension, coronary heart disease, diabetes, cataract, and stroke. Area (OR=0.556; 95% CI, 0.465 to 0.666), region (OR=0.834; 95% CI, 0.723 to 0.962), body mass index (BMI) (OR=1.124; 95% CI, 1.017 to 1.242), and impairment of activities of daily living (OR=0.911; 95% CI, 0.855 to 0.970) were independent factors associated with multimorbidity.

CONCLUSIONS

Multimorbidity is common in older Chinese inpatients with a national prevalence of 69.3% that increases in line with age. Age, region, area, BMI, and daily activities were independent factors significantly associated with multimorbidity in older inpatients. Clinicians should therefore focus more attention on multimorbidity.

Promoting oral HIV self-testing via the internet among men who have sex with men in China: a feasibility assessment

OBJECTIVES

The HIV prevalence among Chinese men who have sex with men (MSM) is high, while the HIV testing rate is low. HIV self-testing (HIVST) is a promising means of scaling up HIV testing among MSM in China, as the ability to test in private is appealing to many individuals. We evaluated the feasibility of promoting oral HIVST via the internet in the MSM population.

METHODS

From April 2013 to April 2014, MSM in two major cities in China were recruited for an observational study with assessment at baseline and follow-up. Data were collected via questionnaire, oral HIVST, and clinic-based HIV confirmatory testing.

RESULTS

A total of 510 MSM were recruited at baseline and 279 (54.7%) returned for a clinic follow-up visit. Compared to MSM recruited via peer referral, those recruited via the internet were better educated, had a higher monthly income, sought and met male sex partners online more frequently, had less often tested or orally tested for HIV before, and being more likely to seek HIV knowledge or HIV intervention information online. The sensitivity of oral HIVST among MSM recruited via the internet was 92.9%, and the specificity was 96.8%. A total of 19.0% of MSM sought both male sex partners and HIV intervention programmes online. The associated factors were > 10 past male sex partners and ever testing for HIV using an oral self-test kit. All MSM who were followed up re-administered oral HIVST, yet fewer MSM recruited via the internet accepted blood retesting than other MSM.

CONCLUSIONS

Promoting oral HIVST via the internet could be a feasible and promising approach to facilitate HIV testing among MSM in China.

Search for Lepton-Flavor Violating Decays B^{+}→K^{+}μ^{±}e^{∓}

A search for the lepton-flavor violating decays B^{+}→K^{+}μ^{±}e^{∓} is performed using a sample of proton-proton collision data, collected with the LHCb experiment at center-of-mass energies of 7 and 8 TeV and corresponding to an integrated luminosity of 3  fb^{-1}. No significant signal is observed, and upper limits on the branching fractions are set as B(B^{+}→K^{+}μ^{-}e^{+})<7.0(9.5)×10^{-9} and B(B^{+}→K^{+}μ^{+}e^{-})<6.4(8.8)×10^{-9} at 90% (95)% confidence level. The results improve the current best limits on these decays by more than one order of magnitude.

The neutron electric dipole moment experiment at the Spallation Neutron Source

Novel experimental techniques are required to make the next big leap in neutron electric dipole moment experimental sensitivity, both in terms of statistics and systematic error control. The nEDM experiment at the Spallation Neutron Source (nEDM@SNS) will implement the scheme of Golub & Lamoreaux [Phys. Rep., 237, 1 (1994)]. The unique properties of combining polarized ultracold neutrons, polarized 3He, and superfluid 4He will be exploited to provide a sensitivity to ∼ 10−28 e · cm. Our cryogenic apparatus will deploy two small (3 L) measurement cells with a high density of ultracold neutrons produced and spin analyzed in situ. The electric field strength, precession time, magnetic shielding, and detected UCN number will all be enhanced compared to previous room temperature Ramsey measurements. Our 3He co-magnetometer offers unique control of systematic effects, in particular the Bloch-Siegert induced false EDM. Furthermore, there will be two distinct measurement modes: free precession and dressed spin. This will provide an important self-check of our results. Following five years of “critical component demonstration,” our collaboration transitioned to a “large scale integration” phase in 2018. An overview of our measurement techniques, experimental design, and brief updates are described in these proceedings.

Measurement of Charged Hadron Production in Z-Tagged Jets in Proton-Proton Collisions at sqrt[s]=8 TeV

The production of charged hadrons within jets recoiling against a Z boson is measured in proton-proton collision data at sqrt[s]=8  TeV recorded by the LHCb experiment. The charged-hadron structure of the jet is studied longitudinally and transverse to the jet axis for jets with transverse momentum p_{T}>20  GeV and in the pseudorapidity range 2.5<η<4. These are the first measurements of jet hadronization at these forward rapidities and also the first where the jet is produced in association with a Z boson. In contrast to previous hadronization measurements at the Large Hadron Collider, which are dominated by gluon jets, these measurements probe predominantly light-quark jets which are found to be more longitudinally and transversely collimated with respect to the jet axis when compared to the previous gluon dominated measurements. Therefore, these results provide valuable information on differences between quarks and gluons regarding nonperturbative hadronization dynamics.

Amplitude Analysis of B^{±}→π^{±}K^{+}K^{-} Decays

The first amplitude analysis of the B^{±}→π^{±}K^{+}K^{-} decay is reported based on a data sample corresponding to an integrated luminosity of 3.0  fb^{-1} of pp collisions recorded in 2011 and 2012 with the LHCb detector. The data are found to be best described by a coherent sum of five resonant structures plus a nonresonant component and a contribution from ππ↔KK S-wave rescattering. The dominant contributions in the π^{±} K^{∓} and K^{+} K^{-} systems are the nonresonant and the B^{±}→ρ(1450)^{0}π^{±} amplitudes, respectively, with fit fractions around 30%. For the rescattering contribution, a sizable fit fraction is observed. This component has the largest CP asymmetry reported to date for a single amplitude of (-66±4±2)%, where the first uncertainty is statistical and the second systematic. No significant CP violation is observed in the other contributions.

Search for the Lepton-Flavor-Violating Decays B_{s}^{0}→τ^{±}μ^{∓} and B^{0}→τ^{±}μ^{∓}

Results are reported from a search for the rare decays B_{s}^{0}→τ^{±}μ^{∓} and B^{0}→τ^{±}μ^{∓}, where the τ lepton is reconstructed in the channel τ^{-}→π^{-}π^{+}π^{-}ν_{τ}. These processes are effectively forbidden in the standard model, but they can potentially occur at detectable rates in models of new physics that can induce lepton-flavor-violating decays. The search is based on a data sample corresponding to 3  fb^{-1} of proton-proton collisions recorded by the LHCb experiment in 2011 and 2012. The event yields observed in the signal regions for both processes are consistent with the expected standard model backgrounds. Because of the limited mass resolution arising from the undetected τ neutrino, the B_{s}^{0} and B^{0} signal regions are highly overlapping. Assuming no contribution from B^{0}→τ^{±}μ^{∓}, the upper limit B(B_{s}^{0}→τ^{±}μ^{∓})<4.2×10^{-5} is obtained at 95% confidence level. If no contribution from B_{s}^{0}→τ^{±}μ^{∓} is assumed, a limit of B(B^{0}→τ^{±}μ^{∓})<1.4×10^{-5} is obtained at 95% confidence level. These results represent the first limit on B(B_{s}^{0}→τ^{±}μ^{∓}) and the most stringent limit on B(B^{0}→τ^{±}μ^{∓}).

Hollow core-shell structured TS-1@S-1 as an efficient catalyst for alkene epoxidation

Hollow core-shell structured TS-1@S-1 zeolite (HCS-TS) was prepared successfully for the first time, which exhibited excellent activity in the epoxidation of alkenes. Combining TEM, UV-vis, UV-Raman, pyridine-IR, solid-state MAS NMR, XPS and so on characterization, the improvement in the catalytic performance of hollow core-shell structured TS-1@S-1 zeolite was credited to the newly formed superior active sites: defective Ti(OSi)₃(OH) species in HCS-TS and six-coordinated titanium active species in uncalcined HCS-TS (HCS-TS^P). Interestingly, these two different titanium active species in the samples could be constructed through calcination or not in the same synthesis process. A possible formation mechanism was investigated in detail; it indicated that the hollowing treatment of TS-1 in the first step was conducive to the construction of the new superior active sites in the samples, and there was a synergistic effect on the formation of these active sites between TPAOH and TEOS in the second step of the synthesis process. This strategy is feasible to enhance the catalytic performance of TS-1, and is suitable for the synthesis of TS-1 on an industrial scale.

Effects of dietary calcium pyruvate on gastrointestinal tract development, intestinal health and growth performance of newly weaned piglets fed low-protein diets

AIM

This study was carried out to investigate the effects of dietary calcium pyruvate supplementation on growth performance and intestinal health of weaned piglets fed low-protein diets.

METHODS AND RESULTS

After a 7-day adaptation period, 60 individually housed piglets (Duroc × Yorkshire-Landrace) weaned at 28 days of age were randomly assigned to receive one of three treatments (20 pigs/treatment) for 28 days: control diet (20·0% crude protein [CP]), low-protein diet (15·5% CP), and experimental (15·5% CP + 1·8% calcium pyruvate). At the end of the experiment, six piglets from each diet group were slaughtered and blood and tissue samples were collected. Compared with the control group, feeding piglets with 15·5% CP decreased the daily body weight gain; lengths of the duodenum, jejunum and ileum; and weights of the stomach, duodenum, jejunum and ileum (P < 0·05), while 15·5% CP + 1·8% calcium pyruvate supplementation removed those differences (P > 0·05). Compared with the control group, the diarrhoea incidence and relative richness of Firmicutes in the colon contents of piglets in both the 15·5% CP and 15·5% CP + 1·8% calcium pyruvate groups was decreased. The relative richness of Bacteriodetes in the colon contents of piglets was higher in the 15·5% CP + 1·8% calcium pyruvate group than in the control and 15·5% CP groups (P < 0·05).

CONCLUSION

Calcium pyruvate supplementation for four weeks removed the negative effects of a low-protein diet on the gastrointestinal tract development and daily body weight gain of weaned piglets.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study showed that supplementing a low-protein diet with calcium pyruvate, an effective alternative metabolic fuel to amino acids, was beneficial in improving the intestinal health and maximizing the growth of newly weaned piglets.

Effects of Rhodotorula mucilaginosa fermentation product on the laying performance, egg quality, jejunal mucosal morphology and intestinal microbiota of hens

AIM

The aim of this study was to investigate the effects of dietary supplementation of Rhodotorula mucilaginosa solid-state fermentation product (RSFP) on the laying performance, egg quality and intestinal microbial flora of hens.

METHODS AND RESULTS

In this study, 40-week-old Roman laying hens (n = 216) were randomly assigned to one of the four groups: the control (CON) group, fed 87.5% basal diet +12.5% fermentation substrate; the 0.5% RSFP group, fed 87.5% basal diet +12.0% fermentation substrate +0.5% RSFP; the 2.5% RSFP group, fed 87.5% basal diet +10.0% fermentation substrate +2.5% RSFP; and the 12.5% RSFP group, fed 87.5% basal diet +12.5% RSFP. The effect of each treatment was analysed in six replicates of nine hens. The experimental period was 31 days, which included a 3-day adaptation period. After 31 days of feeding, one hen from each replicate was randomly selected and killed, and the jejunum and digesta in the cecum were collected for the determination of the intestinal morphology and microbial flora respectively. Daily egg mass in the 2.5 and 12.5% RSFP groups and egg production and feed conversion ratio in the 12.5% RSFP group were higher than those in control group (P < 0.05). The yolk colour was improved in hens fed RSFP-supplemented diets (P < 0.05). Hens fed RSFP-supplemented diet showed a decrease in the relative abundances of Proteobacteria, Bacteroides, Helicobacteraceae, Helicobacter and Lachnospiraceae UCG-002, but an increase in the relative abundance of Prevotellaceae UCG-001 in the cecum (P < 0.05).

CONCLUSION

Dietary RSFP supplementation improved the laying performance, egg quality and intestinal microflora of hens.

SIGNIFICANCE AND IMPACT OF THE STUDY

Dietary supplementing diet with Rhodotorula mucilaginosa solid-state fermentation product, which is rich in carotenoids, improved the yolk colour and increased the carotenoid content, thereby improving the intestinal health of hens.

First Observation of the Directed Flow of D^{0} and D^{0}[over ¯] in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|<0.8) in Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR detector at the Relativistic Heavy Ion Collider. In 10-80% Au+Au collisions, the slope of the v_{1} rapidity dependence (dv_{1}/dy), averaged over D^{0} and D^{0}[over ¯] mesons, is -0.080±0.017(stat)±0.016(syst) for transverse momentum p_{T} above 1.5  GeV/c. The absolute value of D^{0} meson dv_{1}/dy is about 25 times larger than that for charged kaons, with 3.4σ significance. These data give a unique insight into the initial tilt of the produced matter, and offer constraints on the geometric and transport parameters of the hot QCD medium created in relativistic heavy-ion collisions.

Observation of New Resonances in the Λ_{b}^{0}π^{+}π^{-} System

We report the observation of a new structure in the Λ_{b}^{0}π^{+}π^{-} spectrum using the full LHCb data set of pp collisions, corresponding to an integrated luminosity of 9  fb^{-1}, collected at sqrt[s]=7, 8, and 13 TeV. A study of the structure suggests its interpretation as a superposition of two almost degenerate narrow states. The masses and widths of these states are measured to be m_{Λ_{b}(6146)^{0}}=6146.17±0.33±0.22±0.16  MeV,m_{Λ_{b}(6152)^{0}}=6152.51±0.26±0.22±0.16  MeV,Γ_{Λ_{b}(6146)^{0}}=2.9±1.3±0.3  MeV,Γ_{Λ_{b}(6152)^{0}}=2.1±0.8±0.3  MeV,with a mass splitting of Δm=6.34±0.32±0.02  MeV, where the first uncertainty is statistical, the second systematic. The third uncertainty for the mass measurements derives from the knowledge of the mass of the Λ_{b}^{0} baryon. The measured masses and widths of these new excited states suggest their possible interpretation as a doublet of Λ_{b}(1D)^{0} states.