Measurement of the cross section for direct-photon production in association with a heavy quark in pp[over ¯] collisions at sqrt[s]=1.96 TeV

We report on a measurement of the cross section for direct-photon production in association with a heavy quark using the full data set of sqrt[s]=1.96  TeV proton-antiproton collisions corresponding to 9.1  fb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron. The measurements are performed as a function of the photon transverse momentum, covering a photon transverse momentum between 30 and 300 GeV, photon rapidities |yγ|<1.0, a heavy-quark-jet transverse momentum pTjet>20  GeV, and jet rapidities |yjet|<1.5. The results are compared with several theoretical predictions.

Search for pair production of strongly interacting particles decaying to pairs of jets in pp collisions at √s=1.96 TeV

We present a search for the pair production of a narrow nonstandard-model strongly interacting particle that decays to a pair of quarks or gluons, leading to a final state with four hadronic jets. We consider both nonresonant production via an intermediate gluon as well as resonant production via a distinct nonstandard-model intermediate strongly interacting particle. We use data collected by the CDF experiment in proton-antiproton collisions at √[s]=1.96 TeV corresponding to an integrated luminosity of 6.6 fb(-1). We find the data to be consistent with nonresonant production. We report limits on σ(pp[over ¯]→jjjj) as a function of the masses of the hypothetical intermediate particles. Upper limits on the production cross sections for nonstandard-model particles in several resonant and nonresonant processes are also derived.

Microstructure change of ZnO nanowire induced by energetic x-ray radiation and its effect on the field emission properties

The changes in the microstructure of ZnO nanowire were studied after exposure to different radiation doses of energetic x-rays. Detailed structural, composition and optical analyses were carried out. It was found that the surface composition changed and defects were formed in the irradiated ZnO nanowires. The structural change of ZnO nanowires after thermal treatment was also studied and similar defects were observed. It is proposed that phonon-induced localized heating is the main reason for the observed changes in microstructure. Finally, the field emission properties of ZnO nanowires before and after x-ray radiation were studied. It was found that the increase of work function and change in morphology induced by the irradiation were the reasons for the observed change in field emission properties.

Search for supersymmetry with like-sign lepton-tau events at CDF

We present a search for chargino-neutralino associated production using like electric charge dilepton events collected by the CDF II detector at the Fermilab Tevatron in proton-antiproton collisions at sqrt[s] = 1.96 TeV. One lepton is identified as the hadronic decay of a tau lepton, while the other is an electron or muon. In data corresponding to 6.0 fb(-1) of integrated luminosity, we obtain good agreement with standard model predictions and set limits on the chargino-neutralino production cross section for simplified gravity- and gauge-mediated models. As an example, assuming that the chargino and neutralino decays to taus dominate, in the simplified gauge-mediated model we exclude cross sections greater than 300 fb at 95% credibility level for chargino and neutralino masses of 225 GeV/c(2). This analysis is the first to extend the LHC searches for electroweak supersymmetric production of gauginos to high tanβ and slepton next-to-lightest supersymmetric particle scenarios.

Search for resonant top-antitop production in the lepton plus jets decay mode using the full CDF data set

This Letter reports a search for a narrow resonant state decaying into two W bosons and two b quarks where one W boson decays leptonically and the other decays into a quark-antiquark pair. The search is particularly sensitive to top-antitop resonant production. We use the full data sample of proton-antiproton collisions at a center-of-mass energy of 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron, corresponding to an integrated luminosity of 9.45 fb(-1). No evidence for resonant production is found, and upper limits on the production cross section times branching ratio for a narrow resonant state are extracted. Within a specific benchmark model, we exclude a Z' boson with mass, M(Z'), below 915 GeV/c(2) decaying into a top-antitop pair at the 95% credibility level assuming a Z' boson decay width of Γ(Z') = 0.012 M(Z'). This is the most sensitive search for a narrow qq-initiated tt resonance in the mass region below 750 GeV/c(2).

Search for a two-Higgs-boson doublet using a simplified model in pp collisions at sqrt[s] = 1.96 TeV

We present a search for new particles in an extension to the standard model that includes a heavy Higgs boson (H(0)), a lighter charged Higgs boson (H(±)), and an even lighter Higgs boson h(0), with decays leading to a W-boson pair and a bottom-antibottom quark pair in the final state. We use events with exactly one lepton, missing transverse momentum, and at least four jets in data corresponding to an integrated luminosity of 8.7 fb(-1) collected by the CDF II detector in proton-antiproton collisions at sqrt[s]= 1.96 TeV. We find the data to be consistent with standard model predictions and report the results in terms of a simplified Higgs-cascade-decay model, setting 95% confidence level upper limits on the product of cross section and branching fraction from 1.3 pb to 15 fb as a function of H(0) and H(±) masses for m(h)(0) = 126 GeV/c(2).

Measurement of the cross section for prompt isolated diphoton production using the full CDF run II data sample

This Letter reports a measurement of the cross section for producing pairs of central prompt isolated photons in proton-antiproton collisions at a total energy sqrt[s] = 1.96 TeV using data corresponding to 9.5 fb(-1) integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured differential cross section is compared to three calculations derived from the theory of strong interactions. These include a prediction based on a leading order matrix element calculation merged with a parton shower model, a next-to-leading order calculation, and a next-to-next-to-leading order calculation. The first and last calculations reproduce most aspects of the data, thus showing the importance of higher-order contributions for understanding the theory of strong interaction and improving measurements of the Higgs boson and searches for new phenomena in diphoton final states.

Gender difference of childhood overweight and obesity in predicting the risk of incident asthma: a systematic review and meta-analysis

The aims of our meta-analysis were (i) to quantify the predictability of childhood overweight and obesity on the risk of incident asthma; and (ii) to evaluate the gender difference on this relationship. The selection criteria included prospective cohort paediatric studies which use age- and sex-specific body mass index (BMI) as a measure of childhood overweight and the primary outcome of incident asthma. A total of 1,027 studies were initially identified through online database searches, and finally 6 studies met the inclusion criteria. The combined result of reported relative risk from the 6 included studies revealed that overweight children conferred increased risks of incident asthma as compared with non-overweight children (relative risk, 1.19; 95% confidence interval [CI], 1.03-1.37). The relationship was further elevated for obesity vs. non-obesity (relative risk, 2.02; 95% CI, 1.16-3.50). A dose-responsiveness of elevated BMI on asthma incidence was observed (P for trend, 0.004). Obese boys had a significantly larger effect than obese girls (relative risk, boys: 2.47; 95% CI, 1.57-3.87; girls: 1.25; 95% CI, 0.51-3.03), with significant dose-dependent effect. Proposed mechanisms of gender difference could be through pulmonary mechanics, sleep disordered breathing and leptin. Further research might be needed to better understand the exact mechanism of gender difference on the obesity-asthma relationship.

A zebrafish model of PINK1 deficiency reveals key pathway dysfunction including HIF signaling

The PTEN induced putative kinase 1 (PINK1) gene is mutated in patients with hereditary early onset Parkinson's disease (PD). The targets of PINK1 and the mechanisms in PD are still not fully understood. Here, we carried out a high-throughput and unbiased microarray study to identify novel functions and pathways for PINK1. In larval zebrafish, the function of pink1 was inhibited using splice-site morpholino oligonucleotides and the samples were hybridized on a two-color gene expression array. We found 177 significantly altered genes in pink1 morphants compared with the uninjected wildtype controls (log fold change values from -1.6 to +0.9). The five most prominent pathways based on critical biological processes and key toxicological responses were hypoxia-inducible factor (HIF) signaling, TGF-β signaling, mitochondrial dysfunction, RAR activation, and biogenesis of mitochondria. Furthermore, we verified that potentially important genes such as hif1α, catalase, SOD3, and atp1a2a were downregulated in pink1 morphants, whereas genes such as fech, pax2a, and notch1a were upregulated. Some of these genes have been found to play important roles in HIF signaling pathways. The pink1 morphants were found to have heart dysfunction, increased erythropoiesis, increased expression of vascular endothelial growth factors, and increased ROS. Our findings suggest that a lack of pink1 in zebrafish alters many vital and critical pathways in addition to the HIF signaling pathway.

Observation of the production of a W boson in association with a single charm quark

The first observation of the production of a W boson with a single charm quark (c) jet in pp[over ¯] collisions at √s=1.96  TeV is reported. The analysis uses data corresponding to 4.3  fb(-1), recorded with the CDF II detector at the Fermilab Tevatron. Charm quark candidates are selected through the identification of an electron or muon from charm-hadron semileptonic decay within a hadronic jet, and a Wc signal is observed with a significance of 5.7 standard deviations. The production cross section σ(Wc)(p(Tc)>20  GeV/c,|η(c)|<1.5)×B(W→ℓν) is measured to be 13.6(-3.1)(+3.4)  pb and is in agreement with theoretical expectations. From this result the magnitude of the quark-mixing matrix element V(cs) is derived, |V(cs)|=1.08±0.16 along with a lower limit of |V(cs)|>0.71 at the 95% confidence level, assuming that the Wc production through c to s quark coupling is dominant.

Predictors of bloodstream infection associated with permanently implantable venous port in solid cancer patients

BACKGROUND

The purpose of this study is to characterize the risk factors of bloodstream infection (BSI) associated with the use of permanent implantable venous ports (Port-A) in solid cancer patients.

METHODS

Solid cancer patients implanted with a Port-A were prospectively observed for the occurrence of Port-A-associated BSI (PABSI), defined as BSI without other identifiable infection foci. A PABSI risk score was developed using the Cox proportional hazards model.

RESULTS

A total of 415 patients were registered; 88 PABSI episodes occurred in 58 patients (incidence1.05 per 1000 catheter-days). All but one patient had stage IV cancer. Independent predictors of PABSI occurrence included neutropenia, total parenteral nutrition (TPN), chronic steroid use, invasive procedures, postoperative antibiotics, and preoperative antibiotics. A PABSI risk score with a cut-off value of 0 (sensitivity 88.5%, specificity 64.3%) was defined for stage IV cancer patients as follows: neutropenia, +1.350; TPN, +1.256; chronic steroid use, +1.947; preoperative antibiotics, -0.970; postoperative antibiotics, +0.959; and invasive procedures, +1.098. The median PABSI-free survival was 4.47 months for patients with scores ≥ 0 but not reached for patients with scores <0 (P < 0.0001).

CONCLUSION

The PABSI risk score can assist in identifying high-risk solid cancer patients and may assist in designing future preventive strategies.

Compact high-pulse-energy passively Q-switched Nd:YLF laser with an ultra-low-magnification unstable resonator: application for efficient optical parametric oscillator

We exploit an ultra-low-magnification unstable resonator to develop a high-pulse-energy side-pumped passively Q-switched Nd:YLF/Cr⁴⁺:YAG laser with improving beam quality. A wedged laser crystal is employed in the cavity to control the emissions at 1047 nm and 1053 nm independently through the cavity alignment. The pulse energies at 1047 nm and 1053 nm are found to be 19 mJ and 23 mJ, respectively. The peak powers for both wavelengths are higher than 2 MW. Furthermore, the developed Nd:YLF lasers are employed to pump a monolithic optical parametric oscillator for confirming the applicability in nonlinear wavelength conversions.

A bacteria injection scheme for in situ bioaugmentation

This article presents an innovative design for inoculating the desired organisms to stratified geological layers at desired rates during in-situ bioaugmentation. The new delivery system consists of intermittent porous tubes connected in series with impermeable polyethylene tubes that run horizontally in each stratified layer of a contaminated aquifer. A bioaugmentation test using the new delivery system was conducted to inject an enriched culture of Escherichia coli (E. coli). Results of the test indicated that the distribution of E. coli through each porous tube was fairly uniform. A mathematical model previously developed to calculate the distribution of water flow through each porous tube was modified to calculate the distribution of E. coli. Geological layers often have different hydraulic conductivities. By controlling the permeability and the length of porous tubes placed in stratified layers, the new design provides a means to selectively deliver aqueous bacteria to various layers at desired rates according to aquifer heterogeneity.

Measurements of the top-quark mass and the tt cross section in the hadronic τ+jets decay channel at sqrt[s] = 1.96 TeV

We present the first direct measurement of the top-quark mass using tt events decaying in the hadronic τ+jets decay channel. Using data corresponding to an integrated luminosity of 2.2 fb(-1) collected by the CDF II detector in pp collisions at sqrt[s] = 1.96 TeV at the Fermilab Tevatron, we measure the tt cross section, σ(tt), and the top-quark mass, M(top). We extract M(top) from a likelihood based on per-event probabilities calculated with leading-order signal and background matrix elements. We measure σ(tt) = 8.8 ± 3.3(stat) ± 2.2(syst) pb and M(top) = 172.7 ± 9.3(stat) ± 3.7(syst) GeV/c(2).

Search for the standard model Higgs Boson produced in association with top quarks using the full CDF data set

A search is presented for the standard model Higgs boson produced in association with top quarks using the full Run II proton-antiproton collision data set, corresponding to 9.45 fb(-1), collected by the Collider Detector at Fermilab. No significant excess over the expected background is observed, and 95% credibility-level upper bounds are placed on the cross section σ(ttH → lepton + missing transverse energy+jets). For a Higgs boson mass of 125 GeV/c(2), we expect to set a limit of 12.6 and observe a limit of 20.5 times the standard model rate. This represents the most sensitive search for a standard model Higgs boson in this channel to date.

Measurement of the bottom-strange meson mixing phase in the full CDF data set

We report a measurement of the bottom-strange meson mixing phase β(s) using the time evolution of B(s)(0)→J/ψ(→μ(+)μ(-))φ(→K(+)K(-)) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at √s=1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb(-1) of integrated luminosity. We report confidence regions in the two-dimensional space of β(s) and the B(s)(0) decay-width difference ΔΓ(s) and measure β(s)∈[-π/2,-1.51]∪[-0.06,0.30]∪[1.26,π/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of β(s), we also determine ΔΓ(s)=0.068±0.026(stat)±0.009(syst) ps(-1) and the mean B(s)(0) lifetime τ(s)=1.528±0.019(stat)±0.009(syst) ps, which are consistent and competitive with determinations by other experiments.

Precision top-quark mass measurement at CDF

We present a precision measurement of the top-quark mass using the full sample of Tevatron √s = 1.96 TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 fb(-1). Using a sample of tt¯ candidate events decaying into the lepton+jets channel, we obtain distributions of the top-quark masses and the invariant mass of two jets from the W boson decays from data. We then compare these distributions to templates derived from signal and background samples to extract the top-quark mass and the energy scale of the calorimeter jets with in situ calibration. The likelihood fit of the templates from signal and background events to the data yields the single most-precise measurement of the top-quark mass, M(top)=172.85±0.71(stat)±0.85(syst) GeV/c(2).

Randomized clinical trial: efficacy and safety of telbivudine and lamivudine in treatment-naïve patients with HBV-related decompensated cirrhosis

Patients with decompensated cirrhosis owing to chronic hepatitis B viral (HBV) infection have a high morbidity/mortality rate, and the treatment remains a challenge. We studied the safety and efficacy of telbivudine and lamivudine in such patients. This noninferiority, double-blind trial randomized 232 treatment-naive patients with decompensated HBV (1:1) in 80 academic hospitals to receive once-daily telbivudine 600 mg or lamivudine 100 mg for 104 weeks. Primary composite endpoint was proportion of patients with HBV DNA <10 000 copies/mL, normal alanine aminotransferase (ALT) and Child-Turcotte-Pugh score improvement/stabilization at week 52. Response rates using a post hoc modified endpoint (HBV DNA <300 copies/mL [57 IU/mL] and ALT normalization) in intent-to-treat analysis (missing = failure) were 56.3%vs 38.0% after 76 weeks (P = 0.018) and 45.6%vs 32.9% after 104 weeks (P = 0.093) for telbivudine vs lamivudine. Telbivudine treatment was an independent predictive factor for HBV DNA <300 copies/mL and ALT normalization (P = 0.037). Response rates with protocol-defined composite endpoint in intent-to-treat analysis (M = F) were 56.2 vs 54.0% (noninferiority not achieved) and 39.1%vs 36.4% (noninferiority achieved) in telbivudine and lamivudine groups at 52 and 104 weeks. Telbivudine treatment was associated with a significant improvement in glomerular filtration rate compared to lamivudine treatment and was also associated with a trend for improvement in survival (87%vs 79%). No cases of lactic acidosis were reported. Telbivudine compared to lamivudine was associated with a higher rate of patients with both viral suppression and ALT normalization, a trend towards a higher rate of survival and significant improvement in glomerular filtration.

Search for the standard model Higgs boson decaying to a bb pair in events with one charged lepton and large missing transverse energy using the full CDF data set

We present a search for the standard model Higgs boson produced in association with a W boson in sqrt[s]=1.96  TeV pp collision data collected with the CDF II detector at the Tevatron corresponding to an integrated luminosity of 9.45  fb(-1). In events consistent with the decay of the Higgs boson to a bottom-quark pair and the W boson to an electron or muon and a neutrino, we set 95% credibility level upper limits on the WH production cross section times the H→bb branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125  GeV/c(2), we observe (expect) a limit of 4.9 (2.8) times the standard model value.

Measurement of the difference in CP-violating asymmetries in D(0)→K(+)K(-) and D(0)→π(+)π(-) decays at CDF

We report a measurement of the difference (ΔA(CP)) between time-integrated CP-violating asymmetries in D(0)→K(+)K(-) and D(0)→π(+)π(-) decays reconstructed in the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab, corresponding to 9.7  fb(-1) of integrated luminosity. The strong decay D(*+)→D(0)π(+) is used to identify the charm meson at production as D(0) or D[over ¯](0). We measure ΔA(CP)=[-0.62±0.21(stat)±0.10(syst)]%, which differs from zero by 2.7 Gaussian standard deviations. This result supports similar evidence for CP violation in charm-quark decays obtained in proton-proton collisions.

Combined search for the standard model Higgs boson decaying to a bb pair using the full CDF data set

We combine the results of searches for the standard model (SM) Higgs boson based on the full CDF Run II data set obtained from sqrt[s]=1.96  TeV pp collisions at the Fermilab Tevatron corresponding to an integrated luminosity of 9.45  fb(-1). The searches are conducted for Higgs bosons that are produced in association with a W or Z boson, have masses in the range 90-150  GeV/c(2), and decay into bb pairs. An excess of data is present that is inconsistent with the background prediction at the level of 2.5 standard deviations (the most significant local excess is 2.7 standard deviations).

Search for the standard model Higgs boson decaying to a bb pair in events with no charged leptons and large missing transverse energy using the full CDF data set

We report on a search for the standard model Higgs boson produced in association with a vector boson in the full data set of proton-antiproton collisions at sqrt[s]=1.96  TeV recorded by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45  fb(-1). We consider events having no identified charged lepton, a transverse energy imbalance, and two or three jets, of which at least one is consistent with originating from the decay of a b quark. We place 95% credibility level upper limits on the production cross section times standard model branching fraction for several mass hypotheses between 90 and 150  GeV/c(2). For a Higgs boson mass of 125  GeV/c(2), the observed (expected) limit is 6.7 (3.6) times the standard model prediction.

Search for the standard model Higgs boson decaying to a bb pair in events with two oppositely charged leptons using the full CDF data set

We present a search for the standard model Higgs boson produced in association with a Z boson in data collected with the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45  fb(-1). In events consistent with the decay of the Higgs boson to a bottom-quark pair and the Z boson to electron or muon pairs, we set 95% credibility level upper limits on the ZH production cross section times the H→bb branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125  GeV/c(2), we observe (expect) a limit of 7.1 (3.9) times the standard model value.

Cyclophilin A and nuclear factor of activated T cells are essential in cyclosporine-mediated suppression of polyomavirus BK replication

Immunosuppressants have impacts on the development of polyomavirus-associated nephropathy. We previously demonstrated that cyclosporin A (CsA) suppressed polyomavirus BK (BKV) replication. The role of cyclophilin A (CypA) and nuclear factor of activated T cells (NFAT) in CsA-imposed suppression of BKV replication was determined in this study. Results demonstrated that knockdown of CypA but not CypB significantly reduced BKV large T antigen (TAg) expression and BKV titer. Overexpression of CypA reversed CypA siRNA-induced inhibition in BKV TAg expression. In addition, CypA overexpression attenuated the suppressive effect of CsA on TAg expression, suggesting CypA implicated in CsA-mediated anti-BKV effect. Knockdown of NFATc3 abrogated TAg expression, while overexpression of NFATc3 promoted TAg expression and augmented BKV promoter activity. NFATc3 binding to the BKV promoter was verified by chromatin immunoprecipitation assay and electrophoretic mobility shift assay. Renal histology also displayed an increase in NFATc3 expression in tubulointerstitium of BKV-associated nephropathy. Furthermore, overexpression of NFATc3 rescued CsA-mediated inhibition of BKV load and TAg expression. A CsA analog, NIM811, which cannot block NFAT functionality, failed to suppress TAg expression. In conclusion, CypA and NFAT are indispensable in BKV replication. CsA inhibits BKV replication through CypA and NFAT, which may be potential targets of anti-BKV treatment.