First observation of CP violation in the decays of B(s)0 mesons

Using pp collision data corresponding to an integrated luminosity of 1.0 fb(-1) and collected by LHCb in 2011 at a center-of-mass energy of 7 TeV, we report the measurement of direct CP violation in B(s)(0)→K(-)π(+) decays, A(CP)(B(s)(0)→K(-)π(+)=0.27±0.04 (stat)±0.01 (syst), with significance exceeding 5 standard deviations. This is the first observation of CP violation in the decays of B(s)(0) mesons. Furthermore, we provide an improved determination of direct CP violation in B(0)→K(+)π(-) decays, A(CP)(B(0)→K(+)π(-)=-0.080±0.007 (stat)±0.003 (syst), which is the most precise measurement of this quantity to date.

Determination of the X(3872) meson quantum numbers

The quantum numbers of the X(3872) meson are determined to be J(PC)=1(++) based on angular correlations in B(+)→X(3872)K(+) decays, where X(3872)→π(+)π(-)J/ψ and J/ψ→μ(+)μ(-). The data correspond to 1.0 fb(-1) of pp collisions collected by the LHCb detector. The only alternative assignment allowed by previous measurements J(PC)=2(-+) is rejected with a confidence level equivalent to more than 8 Gaussian standard deviations using a likelihood-ratio test in the full angular phase space. This result favors exotic explanations of the X(3872) state.

Search for rare B(0)((s))→μ(+)μ(-)μ(+)μ(-) decays

A search for the decays B(0)((s))→μ(+)μ(-)μ(+)μ(-) and B(0)→μ(+)μ(-)μ(+)μ(-) is performed using data, corresponding to an integrated luminosity of 1.0 fb(-1), collected with the LHCb detector in 2011. The number of candidates observed is consistent with the expected background and, assuming phase-space models of the decays, limits on the branching fractions are set: B(B(s)(0)→μ(+)μ(-)μ(+)μ(-))<1.6(1.2)×10(-8) and B(B(0)→μ(+)μ(-)μ(+)μ(-))<6.6(5.3)×10(-9) at 95% (90%) confidence level. In addition, limits are set in the context of a supersymmetric model which allows for the B((s))(0) meson to decay into a scalar (S) and pseudoscalar particle (P), where S and P have masses of 2.5 GeV/c and 214.3 MeV/c, respectively, both resonances decay into μ(+)μ(-). The branching fraction limits for these decays are B(B(s)(0)→SP)<1.6(1.2)×10(-8) and B(B(0)→SP)<6.3(5.1)×10(-9) at 95% (90%) confidence level.

Measurement of the forward energy flow in pp collisions at [Formula: see text]

The energy flow created in pp collisions at [Formula: see text] is studied within the pseudorapidity range 1.9<η<4.9 with data collected by the LHCb experiment. The measurements are performed for inclusive minimum-bias interactions, hard scattering processes and events with an enhanced or suppressed diffractive contribution. The results are compared to predictions given by Pythia-based and cosmic-ray event generators, which provide different models of soft hadronic interactions.

Measurement of the Λ(b)(0), Ξ (b)(-), and Ω(b((-) Baryon masses

Bottom baryons decaying to a J/ψ meson and a hyperon are reconstructed using 1.0 fb(-1) of data collected in 2011 with the LHCb detector. Significant Λ(b)(0) → J/ψΛ, Ξ(b((-) → J/ψΞ(-) and Ω(b)(-) → J/ψΩ(-) signals are observed and the corresponding masses are measured to be M(Λ(b)(0))=5619.53 ± 0.13(stat.) ± 0.45(syst.) MeV/c(2), M(Ξ(b)(-)) = 5795.8 ± 0.9(stat.) ± 0.4(syst.) MeV/c(2), M(Ω(b)(-)) = 6046.0 ± 2.2(stat.) ± 0.5(syst.) MeV/c(2) , while the differences with respect to the Λ(b)(0) mass are M(Ξ(b)(-))-M(Λ(b)(0))=176.2 ± 0.9(stat.) ± 0.1(syst.) MeV/c(2), M(Ω(b)(-))-M(Λ(b)(0))=426.4 ± 2.2(stat.) ± 0.4(syst.) MeV/c(2). These are the most precise mass measurements of the Λ(b)(0), Ξ(b)(-) and Ω(b)(-) baryons to date. Averaging the above Λ(b)(0) mass measurement with that published by LHCb using 35 pb(-1) of data collected in 2010 yields M(Λ(b)(0)) = 5619.44 ± 0.13(stat.)± 0.38(syst.) MeV/c(2).

First observation of the decay Bs2*(5840)(0)→B*+ K- and studies of excited Bs(0) mesons

The properties of the orbitally excited (L=1) Bs(0) states are studied by using 1.0  fb(-1) of pp collisions at sqrt[s]=7  TeV collected with the LHCb detector. The first observation of the Bs2*(5840)(0) meson decaying to B*+ K- is reported, and the corresponding branching fraction measured relative to the B+ K- decay mode. The Bs1(5830)(0)→B*+ K- decay is observed as well. The width of the Bs2*(5840)(0) state is measured for the first time, and the masses of the two states are determined with the highest precision to date. The observation of the Bs2*(5840)(0)→B*+ K- decay favors the spin-parity assignment J(P)=2+ for the Bs2*(5840)(0) meson. In addition, the most precise measurement of the mass difference m(B*+)-m(B+)=45.01±0.30(stat)±0.23(syst)  MeV/c(2) is obtained.

TCF3, a novel positive regulator of osteogenesis, plays a crucial role in miR-17 modulating the diverse effect of canonical Wnt signaling in different microenvironments

Wnt signaling pathways are a highly conserved pathway, which plays an important role from the embryonic development to bone formation. The effect of Wnt pathway on osteogenesis relies on their cellular environment and the expression of target genes. However, the molecular mechanism of that remains unclear. On the basis of the preliminary results, we observed the contrary effect of canonical Wnt signaling on osteogenic differentiation of periodontal ligament stem cells (PDLSCs) in the different culture environment. Furthermore, we found that the expression level of miR-17 was also varied with the change in the culture environment. Therefore, we hypothesized that miR-17 and canonical Wnt signaling may have potential interactions, particularly the inner regulation relationship in different microenvironments. In this paper, we observed that canonical Wnt signaling promoted osteogenesis of PDLSCs in the fully culture medium, while inhibited it in the osteogenic differentiation medium. Interestingly, alteration in the expression level of endogenous miR-17 could partially reverse the different effect of canonical Wnt signaling. Furthermore, the role of miR-17 was because of its target gene TCF3 (transcription factor 3), a key transcription factor of canonical Wnt pathway. Overexpression of TCF3 attenuated the effect of miR-17 on modulating canonical Wnt signaling. Finally, we elucidated that TCF3 enhanced osteogenesis both in vitro and in vivo. In brief, the different level of miR-17 was the main cause of the different effect of canonical Wnt signaling, and TCF3 was the crucial node of miR-17–canonial Wnt signaling regulation loop. This understanding of microRNAs regulating signaling pathways in different microenvironments may pave the way for fine-tuning the process of osteogenesis in bone-related disorders.

Observation of D0-D0 oscillations

We report a measurement of the time-dependent ratio of D(0) → K(+) π- to D(0) → K(-) π(+) decay rates in D(*+)-tagged events using 1.0 fb(-1) of integrated luminosity recorded by the LHCb experiment. We measure the mixing parameters x('2) = (-0.9 ± 1.3) × 10(-4), y' = (7.2 ± 2.4) × 10(-3), and the ratio of doubly-Cabibbo-suppressed to Cabibbo-favored decay rates R(D) = (3.52 ± 0.15) × 10^{-3}, where the uncertainties include statistical and systematic sources. The result excludes the no-mixing hypothesis with a probability corresponding to 9.1 standard deviations and represents the first observation of D0-D0 oscillations from a single measurement.

First evidence for the decay B(s)(0)→μ+ μ-

A search for the rare decays B(s)(0)→μ+ μ- and B(0)→μ+ μ- is performed with data collected in 2011 and 2012 with the LHCb experiment at the Large Hadron Collider. The data samples comprise 1.1  fb(-1) of proton-proton collisions at sqrt[s]=8  TeV and 1.0  fb(-1) at sqrt[s]=7  TeV. We observe an excess of B(s)(0)→μ+ μ- candidates with respect to the background expectation. The probability that the background could produce such an excess or larger is 5.3×10(-4) corresponding to a signal significance of 3.5 standard deviations. A maximum-likelihood fit gives a branching fraction of B(B(s)(0)→μ+ μ-)=(3.2(-1.2)(+1.5))×10(-9), where the statistical uncertainty is 95% of the total uncertainty. This result is in agreement with the standard model expectation. The observed number of B(0)→μ+ μ- candidates is consistent with the background expectation, giving an upper limit of B(B(0)→μ+ μ-)<9.4×10(-10) at 95% confidence level.

Regional and urban-rural disparities in prevalence of over-weight among old people in China: evidence from four Chinese provinces

OBJECTIVE

This study is a systematic analysis of regional and local (urban-rural) rates of over-weight among elderly people in China. The primary goal is to update the different trends in over-nutrition by gender and location among elderly Chinese.

STUDY DESIGN AND METHODS

Data used for this study were obtained from the comprehensive longitudinal data collected in the most recent waves of the China Health and Nutrition Survey in 2000 and 2006. Comparative data on four provinces, two located in the poorer west (Guangxi, Guizhou) and the other two located in the richer east (Jiangsu, Shandong) were selected from the nine provinces of China participating in the survey. The study population included elderly adults aged 60 years or older interviewed during either of the two survey waves. A total of 1996 individuals (998 in 2000 and 998 in 2006) aged 60 years or older made up the sample for the analysis. We compared changes in body mass index (BMI) with changes in the prevalence of over-nutrition across the 6 years.

RESULTS

The mean BMI values observed ranged from 20.8 kg/m² to 23.2 kg/m². The prevalence of over-weight ranged from 10.5% to 39.0% in both surveys. There were increases in the prevalence of overweight that were greater than the reduction in the prevalence of underweight among Chinese elderly people. Elderly people in the eastern regions and in urban areas were significantly more likely to be overweight compared with those in western regions and rural areas.

CONCLUSION

This study found that the rates of overweight in elderly Chinese increased overall between 2000 and 2006. China must act quickly to curb continued increases in overweight and the associated economic costs, with particular focus on target groups.

Comparison of Preincisional and Postincisional Parecoxib Administration on Postoperative Pain Control and Cytokine Response After Total Hip Replacement

Objective:

To investigate whether preincisional parecoxib administration can reduce postoperative pain and modulate the inflammatory cytokine response to a greater extent than preincisional parecoxib administration in total hip replacement patients.

Methods:

Patients were randomized to receive 40 mg parecoxib intravenously either before or after skin incision (preincisional and postincisional groups, respectively). Morphine was administered for postoperative analgesia. Visual analogue pain scale (VAS) scores and morphine consumption were recorded at 1, 6, 18 and 24 h postoperation. Plasma levels of interleukin (IL)-6, IL-8 and tumour necrosis factor-a were measured 30 min before skin incision and 6 h postoperation.

Results:

Compared with the post - incisional group, VAS pain scores at 1 and 6 h postoperation were significantly lower in the preincisional group. Morphine consumption was significantly lower in the preincisional group at 6, 18 and 24 h postoperation. In both groups, IL-6 and IL- 8 levels increased significantly at 6 h postoperation compared with pre - operation, and the preincisional group had significantly lower levels of IL-6 and IL-8 at 6 h postoperation compared with the postincisional group.

Conclusions:

Preincisional parecoxib administration reduced postoperative pain and morphine consumption compared with post - incisional administration, and attenuated IL-6 and IL-8 production 24 h after hip replacement surgery.

Assessing the potential of candidate DNA barcodes for identifying non-flowering seed plants

In plants, matK and rbcL have been selected as core barcodes by the Consortium for the Barcode of Life (CBOL) Plant Working Group (PWG), and ITS/ITS2 and psbA-trnH were suggested as supplementary loci. Yet, research on DNA barcoding of non-flowering seed plants has been less extensive, and the evaluation of DNA barcodes in this division has been limited thus far. Here, we evaluated seven markers (psbA-trnH, matK, rbcL, rpoB, rpoC1, ITS and ITS2) from non-flowering seed plants. The usefulness of each region was assessed using four criteria: the success rate of PCR amplification, the differential intra- and inter-specific divergences, the DNA barcoding gap and the ability to discriminate species. Among the seven loci tested, ITS2 produced the best results in the barcoding of non-flowering seed plants. In addition, we compared the abilities of the five most-recommended markers (psbA-trnH, matK, rbcL, ITS and ITS2) to identify additional species using a large database of gymnosperms from GenBank. ITS2 remained effective for species identification in a wide range of non-flowering seed plants: for the 1531 samples from 608 species of 80 diverse genera, ITS2 correctly authenticated 66% of them at the species level. In conclusion, the ITS2 region can serve as a useful barcode to discriminate non-flowering seed plants, and this study will contribute valuable information for the barcoding of plant species.

Vascular endothelial growth factor-induced expression of its receptors and activation of the MAPK signaling pathway during ovine oocyte maturation in vitro

The vascular endothelial growth factor (VEGF) has beneficial effects on ovine oocytes during in vitro maturation and their subsequent early embryonic development, but the biochemical pathway underlying this effect has not been elucidated. Therefore, the focus of the present study was to investigate the activation of the mitogen-activated protein kinase (MAPK) pathway in response to the addition of VEGF to the maturation medium, and to study the subcellular localization of VEGF and its receptors during ovine oocyte maturation. We concluded that: (1) VEGF mainly localized in the cytoplasm, whereas its receptors, fms-tyrosine kinase-1 and kinase domain region (KDR), were localized on the plasma membrane of oocytes; (2) the addition of 5 ng/mL VEGF increased the percentage of oocytes with extruded first polar bodies (50.9 ± 2.2% vs. 34.6 ± 2.9%; treatment vs. control, respectively; P < 0.01) and the rate of oocytes competent to undergo nuclear maturation (70.6 ± 0.9% vs. 62.9 ± 1.9%, P < 0.01); and (3) as the expression of VEGF, fms-tyrosine kinase-1, and KDR increased after supplementation with 5 ng/mL, expression of VEGF, mitogen-activated protein kinase kinase (MEK), and MAPK mRNA, as well as MAPK phosphorylation, were stimulated in a time-dependent manner. We inferred that, in a paracrine manner, exogenous VEGF bound to KDR, its main receptor, and then activated the MAPK signaling pathway, which promoted maturation of ovine oocytes. However, the VEGF system also had an autocrine regulatory loop that contributed to creating an environment optimal for oocyte maturation.

Acute biliary pancreatitis treated by early endoscopic intervention

AIM

Acute biliary pancreatitis (ABP) is a worldwide disease. The aim of this study was to investigate the clinical efficacy of early endoscopic treatment of ABP.

METHODS

From 2004 to 2010, 120 inpatients (42 male, 78 female) with ABP were randomly divided into two groups, each of which contains 60 patients. Before the intervention, patients in the two groups did not show significant differences in the age, gender, APACHE-II score, CT grading and other clinical characteristics. The early intervention group was managed with endoscopic treatment within 72 h after the initial symptom, whereas no endoscopic treatment for the control group. The mortality, complication rate, hospital stay, and the costs were compared.

RESULTS

Compared with the control group, the complication rate (10% vs. 26.7%, experiment group vs. control group, the same hereinafter) and the time of pain relief (2.36±1.91 d vs. 6.52±2.39 d), time of bellyache disappeared (5.95±1.81 d vs. 7.66±3.01 d), time of temperature recovery (3.74±2.06 d vs. 5.33±2.15 d), and hospital stay (18.3±4.1 d vs. 27.1±14.6 d) of the experiment group were all shortened (P<0.05). However, the mortality (1.7% vs. 10%, P>0.1), time of serum amylase recovery (3.98±2.02 d vs. 5.11±2.22 d, P>0.1), and hospital costs (P>0.1) did not show significant difference. Early endoscopic treatment can reduce the complication of ABP and shorten the hospital stay. It could be adopted as the preferred treatment for ABP in hospitals.

Transgastric endoscopic gastroenterostomy using a partially covered occluder: a canine feasibility study

BACKGROUND AND STUDY AIMS

The use of natural orifice transluminal endoscopic surgery (NOTES) for gastroenterostomy has been previously reported, but it remains technically challenging and additional assistance is often needed. The aim of this study was to develop and evaluate a novel method for the creation of a gastroenterostomy using NOTES with an occluder.

METHODS

Transgastric endoscopic gastroenterostomy was performed in 12 healthy female dogs using a therapeutic upper gastrointestinal endoscope and a partially covered occluder. The occluder was removed with a snare 1 week later. The patency of the gastroenterostomy was confirmed by endoscopy, contrast radiological study, necropsy, and histological examination after 2 weeks.

RESULTS

NOTES gastroenterostomy with an occluder was successful in all 12 dogs. The mean operative time was 32.3 ± 10.3 min (range 20.3 - 53.5). One dog (the first; 8.3 %) died 4 days after the operation of severe intra-abdominal infection due to incorrect deployment of the occluder and poor bowel preparation. Minor bleeding occurred at the anastomosis after removal of the occluder in two of the remaining dogs (18.2 %). Necropsy revealed postoperative adhesions that had developed at the anastomotic site in one dog (9.1 %). No anastomotic leakage or intestinal obstruction was observed. Complete healing of the anastomosis was confirmed on histological evaluation.

CONCLUSION

Gastroenterostomy performed entirely by NOTES using an occluder was technically feasible in this survival animal model.

Response to the first wave of pandemic (H1N1) 2009: experiences and lessons learnt from China

More than 2 years after the start of pandemic H1N1, the world is fortunate that the impact, to date, has been moderate. An evaluation of the global response to the first wave of the pandemic is still ongoing. The results of an analysis of the situation in China is presented in order to gain a better understanding of the episode; to summarize the experiences in preparedness, control and mitigation of the pandemic; and to identify issues for further consideration and investigation in order to improve the response to possible next waves of the pandemic. China's response shows how a huge challenge can be transformed into an opportunity, and may offer some valuable lessons to face another wave of the pandemic or other potential public health emergencies in the future, not only for China but also for the international community.

Observation of a low-symmetry phase in Na0.5Bi0.5TiO3crystals by optical birefringence microscopy

Single crystals of sodium bismuth titanate (Na0.5Bi0.5TiO3, NBT) (pure and Mn-doped) have been investigated by means of optical birefringence microscopy. For both crystals, it was found that, above ∼573 K, the optical axis is perfectly aligned with one of the pseudocubic 〈001〉PCdirections, while the domain walls appearing in the images are parallel to the pseudocubic 〈011〉PCdirections. These observations are consistent with a tetragonal symmetry. Below ∼573 K, the observed optical orientation of both crystals shows a broad angular distribution, with no clearly visible crystallographically oriented domain walls. These results are consistent with monoclinic symmetry. Most importantly, the direct observation of the temperature-driven rotation of the optical axis within the monoclinic plane is reported for the first time in a perovskite oxide material, in the present case for Mn-doped NBT. This has consequences for the understanding of phase transitions in technologically relevant compounds, such as PbZr1−xTixO3, which are considered to have monoclinic structure in some parts of the phase diagram.

454 EST analysis detects genes putatively involved in ginsenoside biosynthesis in Panax ginseng

Panax ginseng C.A. Meyer is one of the most highly valued medicinal plants in the world. To analyze the transcriptome of P. ginseng and discover the genes involved in ginsenoside biosynthesis, cDNAs derived from the total RNA of 11-year-old, wood-grown P. ginseng roots were analyzed by 454 sequencing. A total of 217,529 high quality reads (expressed sequence tags, ESTs), with an average length of 409 bases, were generated from a one-quarter run to yield 31,741 unique sequences. The majority (20,198; 63.6%) of the unique sequences were annotated using BLAST similarity searches. A total of 16,810 and 16,577 unique sequences were assigned to functional classifications and biochemical pathways based on Gene Ontology analysis and the Kyoto Encyclopedia of Genes and Genomes assignment, respectively. Nine genes involved in the biosynthesis of ginsenoside skeletons and many candidate genes putatively responsible for modification of the skeletons, including 133 cytochrome P450s and 235 glycosyltransferases, were identified. From these candidates, six transcripts encoding UDP-glycosyltransferases that were most likely to be involved in ginsenoside biosynthesis were selected. These results open a new avenue by which to explore and exploit biosynthetic and biochemical properties that may lead to drug improvement. These 454 ESTs will provide the foundation for further functional genomic research into the traditional herb P. ginseng or its closely related species.