Measurement of the Mass Difference Between Neutral Charm-Meson Eigenstates

We report a measurement of the mass difference between neutral charm-meson eigenstates using a novel approach that enhances sensitivity to this parameter. We use 2.3×10^{6} D^{0}→K_{S}^{0}π^{+}π^{-} decays reconstructed in proton-proton collisions collected by the LHCb experiment in 2011 and 2012. Allowing for CP violation in mixing and in the interference between mixing and decay, we measure the CP-averaged normalized mass difference x_{CP}=[2.7±1.6(stat)±0.4(syst)]×10^{-3} and the CP-violating parameter Δx=[-0.53±0.70(stat)±0.22(syst)]×10^{-3}. The results are consistent with CP symmetry. These determinations are the most precise from a single experiment and, combined with current world-average results, yield the first evidence that the masses of the neutral charm-meson eigenstates differ.

The bHLH Protein Nulp1 is Essential for Femur Development Via Acting as a Cofactor in Wnt Signaling in Drosophila

Background:

The basic helix-loop-helix (bHLH) protein families are a large class of transcription factors, which are associated with cell proliferation, tissue differentiation, and other important development processes. We reported that the Nuclear localized protein-1 (Nulp1) might act as a novel bHLH transcriptional factor to mediate cellular functions. However, its role in development in vivo remains unknown.

Methods:

Nulp1 (dNulp1) mutants are generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal. Expression of Wg target genes are analyzed by qRT-PCR. We use the Top-Flash luciferase reporter assay to response to Wg signaling.

Results:

Here we show that Drosophila Nulp1 (dNulp1) mutants, generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal, are partially homozygous lethal and the rare escapers have bent femurs, which are similar to the major manifestation of congenital bent-bone dysplasia in human Stuve-Weidemann syndrome. The fly phenotype can be rescued by dNulp1 over-expression, indicating that dNulp1 is essential for fly femur development and survival. Moreover, dNulp1 overexpression suppresses the notch wing phenotype caused by the overexpression of sgg/GSK3β, an inhibitor of the canonical Wnt cascade. Furthermore, qRT-PCR analyses show that seven target genes positively regulated by Wg signaling pathway are down-regulated in response to dNulp1 knockout, while two negatively regulated Wg targets are up-regulated in dNulp1 mutants. Finally, dNulp1 overexpression significantly activates the Top-Flash Wnt signaling reporter.

Conclusion:

We conclude that bHLH protein dNulp1 is essential for femur development and survival in Drosophila by acting as a positive cofactor in Wnt/Wingless signaling.

Observation of a Narrow Pentaquark State, P_{c}(4312)^{+}, and of the Two-Peak Structure of the P_{c}(4450)^{+}

A narrow pentaquark state, P_{c}(4312)^{+}, decaying to J/ψp, is discovered with a statistical significance of 7.3σ in a data sample of Λ_{b}^{0}→J/ψpK^{-} decays, which is an order of magnitude larger than that previously analyzed by the LHCb Collaboration. The P_{c}(4450)^{+} pentaquark structure formerly reported by LHCb is confirmed and observed to consist of two narrow overlapping peaks, P_{c}(4440)^{+} and P_{c}(4457)^{+}, where the statistical significance of this two-peak interpretation is 5.4σ. The proximity of the Σ_{c}^{+}D[over ¯]^{0} and Σ_{c}^{+}D[over ¯]^{*0} thresholds to the observed narrow peaks suggests that they play an important role in the dynamics of these states.

Sufficient direction factor model and its application to gene expression quantitative trait loci discovery

Rapid improvement in technology has made it relatively cheap to collect genetic data, however statistical analysis of existing data is still much cheaper. Thus, secondary analysis of single-nucleotide polymorphism, SNP, data, i.e., reanalysing existing data in an effort to extract more information, is an attractive and cost-effective alternative to collecting new data. We study the relationship between gene expression and SNPs through a combination of factor analysis and dimension reduction estimation. To take advantage of the flexibility in traditional factor models where the latent factors are not required to be normal, we recommend using semiparametric sufficient dimension reduction methods in the joint estimation of the combined model. The resulting estimator is flexible and has superior performance relative to the existing estimator, which relies on additional assumptions on the latent factors. We quantify the asymptotic performance of the proposed parameter estimator and perform inference by assessing the estimation variability and by constructing confidence intervals. The new results enable us to identify, for the first time, statistically significant SNPs concerning gene-SNP relations in lung tissue from genotype-tissue expression data.

Observation of CP Violation in Charm Decays

A search for charge-parity (CP) violation in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is reported, using pp collision data corresponding to an integrated luminosity of 5.9  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D^{*}(2010)^{+}→D^{0}π^{+} decays or from the charge of the muon in B[over ¯]→D^{0}μ^{-}ν[over ¯]_{μ}X decays. The difference between the CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is measured to be ΔA_{CP}=[-18.2±3.2(stat)±0.9(syst)]×10^{-4} for π-tagged and ΔA_{CP}=[-9±8(stat)±5(syst)]×10^{-4} for μ-tagged D^{0} mesons. Combining these with previous LHCb results leads to ΔA_{CP}=(-15.4±2.9)×10^{-4}, where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of CP violation in the decay of charm hadrons.

Search for CP Violation in D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} Decays

A search for charge-parity (CP) violation in Cabibbo-suppressed D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} decays is reported using proton-proton collision data, corresponding to an integrated luminosity of 3.8  fb^{-1}, collected at a center-of-mass energy of 13 TeV with the LHCb detector. High-yield samples of kinematically and topologically similar Cabibbo-favored D_{(s)}^{+} decays are analyzed to subtract nuisance asymmetries due to production and detection effects, including those induced by CP violation in the neutral kaon system. The results areA_{CP}(D_{s}^{+}→K_{S}^{0}π^{+})=(1.3±1.9±0.5)×10^{-3},A_{CP}(D^{+}→K_{S}^{0}K^{+})=(-0.09±0.65±0.48)×10^{-3},A_{CP}(D^{+}→ϕπ^{+})=(0.05±0.42±0.29)×10^{-3},where the first uncertainties are statistical and the second systematic. They are the most precise measurements of these quantities to date, and are consistent with CP symmetry. A combination with previous LHCb measurements, based on data collected at 7 and 8 TeV, is also reported.

Observation of B_{(s)}^{0}→J/ψpp[over ¯] Decays and Precision Measurements of the B_{(s)}^{0} Masses

The first observation of the decays B_{(s)}^{0}→J/ψpp[over ¯] is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2  fb^{-1}, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are B(B^{0}→J/ψpp[over ¯])=[4.51±0.40(stat)±0.44(syst)]×10^{-7}, B(B_{s}^{0}→J/ψpp[over ¯])=[3.58±0.19(stat)±0.39(syst)]×10^{-6}. For the B_{s}^{0} meson, the result is much higher than the expected value of O(10^{-9}). The small available phase space in these decays also allows for the most precise single measurement of both the B^{0} mass as 5279.74±0.30(stat)±0.10(syst)  MeV and the B_{s}^{0} mass as 5366.85±0.19(stat)±0.13(syst)  MeV.

Search for Lepton-Universality Violation in B^{+}→K^{+}ℓ^{+}ℓ^{-} Decays

A measurement of the ratio of branching fractions of the decays B^{+}→K^{+}μ^{+}μ^{-} and B^{+}→K^{+}e^{+}e^{-} is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0  fb^{-1} recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1<q^{2}<6.0  GeV^{2}/c^{4} the ratio of branching fractions is measured to be R_{K}=0.846_{-0.054}^{+0.060}_{-0.014}^{+0.016}, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of R_{K} to date and is compatible with the standard model at the level of 2.5 standard deviations.

[Prevalence and quality of spirometry and the impact of spirometry training in Hunan, People's Republic of China]

Objective: To explore quality of spirometry in Hunan province and the impact of education on it. Methods: Cross-sectional study and a prospective randomized cohort study. (1) A total of 460 public hospitals in Hunan province were investigated. Research assistants collected 20 consecutive reports of pulmonary ventilation test reports (PVTRs) and basal information of those hospitals which owned spirometry. (2) To measure the effect of education, 28 randomly selected 2(nd) level hospitals which owned spirometry were randomized to intervention and control group (1∶1). The intervention group received a short-time training which included face-to-face lectures and a hand-by-hand operation training course, while the control group received usual care. PVTRs were investigated 3 months after the intervention. All PVTRs were classified to grade A, B, C, D and E according to the Chinese pulmonary ventilation test (PVT) guidelines. Results: The recovery rate was 100%. The spirometry-equipped ratio was 1.6% (2/129) at 1(st) level hospitals, 39.0% (105/269) at 2(nd) level hospitals, 100% (62/62) at 3(rd) level hospitals in Hunan province. There were 100% (2/2), 91.4% (96/105) and 93.5% (58/62) utilization rate at 1(st), 2(nd) and 3(rd) level hospitals. Common reasons for not owning a spirometer were equipment cost and insufficient insurance. Lack of knowledge about spirometry and inadequate benefits were the top two reasons for low utilization rate. There were 3 120 PVTRs from 156 hospitals which used spirometry, a total of 50.4% (1 574/3 120) PVTRs got grade A, a total of 14.8% (462/3 120) PVTRs were judged as unreliable (grade D, E). There were 560 PVTRs and 28 questionnaires, respectively, before and after intervention. The technicians' knowledge improved after education compared to before (9.8±0.6 vs 8.6±1.1) (P<0.05). And 75.0% (210/280) PVTRs got A grade in the intervention group, which was significantly higher than those in the control group (75.0% vs 37.9%, P<0.05). While none of PVTRs was unreliable, which was lower than that in the control group (0 vs 14.6%, P<0.05). Conclusions: The equipment ratio and the utilization rate of spirometry are still low and imbalanced among three levels hospitals in Hunan. The short-time training is helpful to improve quality of spirometry.

MiR-34a suppresses HNSCC growth through modulating cell cycle arrest and senescence

MiR-34a acts as a tumor suppressor in various malignancies. In HNSCC, the role of miR-34a in proliferation has not been fully elaborated and the target genes are still bind. Here, we addressed that forced miR-34a expression induced cell cycle arrest and senescence. Hypoxia/HIF1α was found to negatively correlate to the expression of miR-34a in HNSCC tissues and partially reverse miR-34a-imposed cell senescence through suppressing miR-34a expression. In order to screen the possible target genes of miR-34a in HNSCC, the differential genes mediated by miR-34a were screened by mRNA microarray. There were 91 genes co-down regulated in two cell lines, which were closely associated with MAPK, ErbB and p53 pathways. Genes, including FUT1, AXL, and MAP2K1 were finally identified as the novel targets of miR-34a by qPCR and luciferase assay. These findings indicate that miR-34a plays an essential role in suppressing HNSCC growth through inducing cell cycle arrest and senescence, by targeting proliferation-associated genes.

Model-Independent Observation of Exotic Contributions to B^{0}→J/ψK^{+}π^{-} Decays

An angular analysis of B^{0}→J/ψK^{+}π^{-} decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3  fb^{-1} collected with the LHCb detector. The m(K^{+}π^{-}) spectrum is divided into fine bins. In each m(K^{+}π^{-}) bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by K^{*} resonances is examined, making minimal assumptions about the K^{+}π^{-} system. The data reject the K^{*}-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the m(J/ψπ^{-}) vs m(K^{+}π^{-}) plane suggests structures near m(J/ψπ^{-})=4200 and 4600 MeV.

First Measurement of Charm Production in its Fixed-Target Configuration at the LHC

The first measurement of heavy-flavor production by the LHCb experiment in its fixed-target mode is presented. The production of J/ψ and D^{0} mesons is studied with beams of protons of different energies colliding with gaseous targets of helium and argon with nucleon-nucleon center-of-mass energies of sqrt[s_{NN}]=86.6 and 110.4 GeV, respectively. The J/ψ and D^{0} production cross sections in pHe collisions in the rapidity range [2, 4.6] are found to be σ_{J/ψ}=652±33(stat)±42(syst)   nb/nucleon and σ_{D^{0}}=80.8±2.4(stat)±6.3(syst)  μb/nucleon, where the first uncertainty is statistical and the second is systematic. No evidence for a substantial intrinsic charm content of the nucleon is observed in the large Bjorken-x region.

The efficacy of the Dietary Approaches to Stop Hypertension diet with respect to improving pregnancy outcomes in women with hypertensive disorders

BACKGROUND

The DASH (Dietary Approaches to Stop Hypertension) diet serves as a dietary pattern for the prevention and control of hypertension. The present study aimed to investigate whether the DASH diet can improve the outcomes of pregnancy with gestational hypertension (GH) and chronic hypertension.

METHODS

The current randomised controlled clinical trial was performed in 85 pregnant women diagnosed with GH and chronic hypertension between July 2015 and December 2017. The women were categorised into a control group (41 cases) and a DASH group (44 cases). Participants were followed until delivery. The clinical outcomes of mothers included gestational weeks of birth, delivery mode, postpartum haemorrhage and GH, as well as the incidence of pre-eclampsia during the second and third trimesters. Newborn measurements were collected by evaluating prematurity, birth weight, body length and neonatal Apgar score.

RESULTS

The incidence of pre-eclampsia, prematurity and low birth weight in the DASH group was lower than that in the control group (P < 0.05). Significant differences were also observed in gestational age at delivery and the newborn body length between the two groups (P < 0.05). We failed to find a significant difference in changes of delivery mode, postpartum haemorrhage, postpartum GH, mean birth weight and Apgar score (P > 0.05) between the two diets.

CONCLUSIONS

A DASH diet might comprise a potential strategy for improving the clinical outcomes in pregnant women with GH and chronic hypertension. Future robust clinical trials are warranted to corroborate these findings.

[Impact of allergic airway diseases on risk of attention deficit hyperactivity disorder in school-age children]

Objective: To investigate the impact of allergic airway diseases on the risk of attention deficit hyperactivity disorder (ADHD) in school-age children. Method: Used stratified cluster sampling method, school-age children in first to sixth grade in primary schools in 9 randomly selected cities including Shanghai, Guangzhou, Xi'an, and Wuhan were enrolled in the study. Interview of parents with questionnaires, which included school-age individual and family social environment questionnaire (including history of diagnosed ADHD, allergic rhinitis, and bronchial asthma) and Children's Sleep Habits Questionnaire (CSHQ), were finished and collected during November to December in 2005.Diagnosed allergic rhinitis and asthma by specialist were independent variables and divided into following three categories as no allergic diseases (neither allergic rhinitis nor asthma), single allergic disease (allergic rhinitis or asthma), and combined allergic diseases (allergic rhinitis and asthma). Diagnosed ADHD as dependent variable, binary logistic regress model was used to analyze the risks of ADHD in school-age children. Result: Totally 23 791 questionnaires were handed out, while 22 018 were collected. The children had an average age of (8.8±1.8) years, within which 10 869 were male, and 11 021 were female. The risk ratios of ADHD were 2.197 (95%CI: 1.823-2.648) and 3.150 (95%CI: 2.082-4.760) in children with single allergic disease and combined allergic diseases separately. There was no significant difference after adjusting for the factor of sleep habits, as the risk ratios were 2.055 (95%CI: 1.683-2.508) and 3.140 (95%CI: 2.061-4.784) in children with single and combined allergic airway disease separately. Conclusion: Allergic rhinitis and bronchial asthma increased the risk of ADHD, not depending on sleep habits. Hence, allergic airway diseases could be independent risk factors of ADHD.

[A cohort study on the association between dynamics of thyroid volume and the changes of physical growth as well as the comparison of different thyroid volume indexes in school-aged children]

Objectives: To investigate the association between the dynamics of thyroid volume and the changes of physical growth in school-aged children as well as to compare the applicability of different thyroid volume indexes, so as to explore more reliable methods for the assessment of thyroid volume. Methods: In October 2012, a multi-stage cluster sampling method was used to select a primary school in Minhang district of Shanghai, Haimen city of Jiangsu province and Yuhuan city of Zhejiang province, respectively. In these areas, a total number of 784 students aged 8-10 years were enrolled in the cohort. Demographic data was collected, while height and weight were measured, with BMI and body surface area (BSA) were calculated. Thyroid volume was examined by B-ultrasonography. Height volume index (HVI), weight and height volume index (WHVI), BMI volume index (BMIV) and BSA volume index (BSAV) were all applied to correct the thyroid volume. All students were followed up, one year later. Results: A total of 769 students with complete data on thyroid volume and physical growth were enrolled, including 378 boys (49.16%) and 391 girls (50.84%). Thyroid volume showed an increase with age, while growth of thyroid volume reduced with the increase of age (P<0.001). The thyroid volume showed a correlation with the changes of physical growth. The growth of height appeared as the dominant influencing factor for thyroid volume growth in those aged 8 and 10 years (P<0.05), while the growth of weight, BMI and BSA were all influencing factors for thyroid volume on students aged 9 years (P<0.05). Conclusions: Thyroid volume in school-aged children was a factor not only associated with age but also with physical growth which had not been considered in the currently used criteria. The inclusion of items as iodine intake, age, physical growth into the thyroid volume indexes seemed to be more reliable, in practice. For the assessment of goiter, HVI for students aged 8 and 10 years and BMIV for students aged 9 years might serve as better indicators.

Measurement of the Charm-Mixing Parameter y_{CP}

A measurement of the charm-mixing parameter y_{CP} using D^{0}→K^{+}K^{-}, D^{0}→π^{+}π^{-}, and D^{0}→K^{-}π^{+} decays is reported. The D^{0} mesons are required to originate from semimuonic decays of B^{-} and B[over ¯]^{0} mesons. These decays are partially reconstructed in a data set of proton-proton collisions at center-of-mass energies of 7 and 8 TeV collected with the LHCb experiment and corresponding to an integrated luminosity of 3  fb^{-1}. The y_{CP} parameter is measured to be (0.57±0.13(stat)±0.09(syst))%, in agreement with, and as precise as, the current world-average value.

Observation of Two Resonances in the Λ_{b}^{0}π^{±} Systems and Precise Measurement of Σ_{b}^{±} and Σ_{b}^{*±} Properties

The first observation of two structures consistent with resonances in the final states Λ_{b}^{0}π^{-} and Λ_{b}^{0}π^{+} is reported using samples of pp collision data collected by the LHCb experiment at sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3  fb^{-1}. The ground states Σ_{b}^{±} and Σ_{b}^{*±} are also confirmed and their masses and widths are precisely measured.

Evidence for an η c ( 1 S ) π - resonance in B 0 → η c ( 1 S ) K + π - decays

A Dalitz plot analysis of B 0 → η c ( 1 S ) K + π - decays is performed using data samples of pp collisions collected with the LHCb detector at centre-of-mass energies of s = 7 , 8 and 13 Te V , corresponding to a total integrated luminosity of 4.7 fb - 1 . A satisfactory description of the data is obtained when including a contribution representing an exotic η c ( 1 S ) π - resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are 4096 ± 20 - 22 + 18 Me V and 152 ± 58 - 35 + 60 Me V , respectively. The spin-parity assignments J P = 0 + and J P = 1 - are both consistent with the data. In addition, the first measurement of the B 0 → η c ( 1 S ) K + π - branching fraction is performed and gives B ( B 0 → η c ( 1 S ) K + π - ) = ( 5.73 ± 0.24 ± 0.13 ± 0.66 ) × 10 - 4 , where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions.

Search for lepton-flavour-violating decays of Higgs-like bosons

A search is presented for a Higgs-like boson with mass in the range 45 to 195 GeV / c 2 decaying into a muon and a tau lepton. The dataset consists of proton-proton interactions at a centre-of-mass energy of 8 TeV , collected by the LHCb experiment, corresponding to an integrated luminosity of 2 fb - 1 . The tau leptons are reconstructed in both leptonic and hadronic decay channels. An upper limit on the production cross-section multiplied by the branching fraction at 95% confidence level is set and ranges from 22 pb for a boson mass of 45 GeV / c 2 to 4 pb for a mass of 195 GeV / c 2 .

Cesarean section and risks of overweight and obesity in school-aged children: a population-based study

BACKGROUND

Obesity puts a great health burden in the world. Previous studies suggest that caesarean section (CS) may increase the risk of obesity in children, but it is still uncertain whether this association is causal or due to residual confounding by medical indication.

AIM

To assess the association between CS, CS without medical indications in particular and the risk of overweight and obesity in school-aged children.

DESIGN

Cross-sectional survey.

METHODS

The 2014 Shanghai Child Health, Education and Lifestyle Evaluation was a large population-based survey with cluster random probability sampling in 26 primary schools in Shanghai, China, in 2014. The mode of delivery was reported by parents. The height, weight and waist circumference of the children were measured. Logistic regression models with SURVEYLOGISTIC procedure were used to estimate the risk of childhood obesity. Pupils delivered vaginally were served as the reference group.

RESULTS

A total of 17 571 pupils completed this survey, and 13 724 of them who were singleton, born term and between 5 and 13 years old were included in our analysis. CS was associated with increased risks of overweight and obesity (BMI: adjusted OR = 1.28 [95%CI 1.13-1.45] and 1.44 [1.26-1.66], respectively; weight for height ratio [WHtR] >0.46: 1.33 [1.20-1.48]). Similar results were found in CS without medical indication (BMI: overweight = 1.24 [1.05-1.47], obesity = 1.43 [1.19-1.72]; WHtR > 0.46: 1.30 [1.13-1.50]).

CONCLUSIONS

CS overall and CS without medical indications were associated with increased risks of overweight and obesity in primary school children.

Measurement of Antiproton Production in p-He Collisions at sqrt[s_{NN}]=110 GeV

The cross section for prompt antiproton production in collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest is measured with the LHCb experiment from a data set corresponding to an integrated luminosity of 0.5  nb^{-1}. The target is provided by injecting helium gas into the LHC beam line at the LHCb interaction point. The reported results, covering antiproton momenta between 12 and 110  GeV/c, represent the first direct determination of the antiproton production cross section in p-He collisions, and impact the interpretation of recent results on antiproton cosmic rays from space-borne experiments.