A search for new dielectron mass resonances using data recorded by the CDF II detector and corres... more A search for new dielectron mass resonances using data recorded by the CDF II detector and corresponding to an integrated luminosity of 5.7 fb −1 is presented. No significant excess over the expected standard model prediction is observed. In this dataset, an event with the highest dielectron mass ever observed (960 GeV/c 2 ) was recorded. The results are interpreted in the Randall-Sundrum (RS) model. Combined with the 5.4 fb −1 diphoton analysis, the RS-graviton lower mass limit for the coupling k/M P l = 0.1 is 1058 GeV/c 2 , making it the strongest limit to date.
This letter reports a measurement of the top quark mass, Mtop, in data from pp collisions at √ s ... more This letter reports a measurement of the top quark mass, Mtop, in data from pp collisions at √ s = 1.96 TeV corresponding to 2.7 fb −1 of integrated luminosity at the Fermilab Tevatron using the CDF II detector. Events with the lepton+jets topology are selected. An unbinned likelihood is constructed based on the dependence of the lepton transverse momentum, PT, on Mtop. A maximum likelihood fit to the data yields a measured mass Mtop = 176.9 ± 8.0stat ± 2.7syst GeV/c 2 . In this measurement, the contribution by the jet energy scale uncertainty to the systematic error is negligible. The result provides an important consistency test for other Mtop measurements where explicit use of the jet energy is made for deriving the top quark mass. * Deceased † With visitors from
C-reactive protein (CRP), an inflammation marker, is a strong independent risk factor for cardiov... more C-reactive protein (CRP), an inflammation marker, is a strong independent risk factor for cardiovascular disease. Vessels are able to express CRP; however, the molecular mechanism behind this expression is not clear. Reverse transcription PCR and ELISA were used to detect messenger RNA and proteins of CRP and nuclear factor κB (NF-κB) activity in vessel rings stretched with different mechanical strains. Interleukin (IL)-6 treatment did not induce CRP expression in vessel rings of white rabbits in the absence of mechanical strain. In contrast, IL-6 augmented CRP expression in vessel rings stretched with mechanical strains of 3 and 5 g (CRP mRNA, IL-6: 11.367±1.68 and 12.78±0.76 vs vehicle: 7.27±0.88 and 8.3±0.91 folds, respectively; CRP, IL-6: 12.79±1.62 and 14.05±2.1 vs vehicle: 7.72±1.04 and 8.16±1.52 folds, respectively; p<0.05 vs 0 g group and vehicle control group; n=5), and this effect was completely blocked by treatment with gadolinium III chloride hexahydrate (GdCl3). Moreover, IL-6 treatment increased NF-κB activity in vessels stretched with a mechanical strain of 3 g, and this effect was blocked by stretch-activated channel inhibitors (streptomycin or GdCl3) and the NF-κB peptide inhibitor SN50, but not by the inactive SN50 analogue SN50M. We also performed similar experiments on human internal mammary arteries and obtained similar results. These results indicate that the inflammatory cytokine IL-6 alone does not induce CRP synthesis in vessels in the absence of mechanical strain; however, IL-6 augments mechanical strain-induced CRP synthesis in vessels via the stretch-activated channel-NF-κB pathway.
In the haplodiploid Hymenoptera, haploid males arise from unfertilized eggs, receiving a single s... more In the haplodiploid Hymenoptera, haploid males arise from unfertilized eggs, receiving a single set of maternal chromosomes while diploid females arise from fertilized eggs and receive both maternal and paternal chromosomes. Under single-locus complementary sex determination (sl-CSD), sex is determined by multiple alleles at a single locus. Sex locus heterozygotes develop as females, while hemizygous and homozygous eggs develop as haploid and diploid males, respectively. Diploid males, which are inviable or sterile in almost all cases studied, are therefore produced in high frequency under inbreeding or in populations with low sex allele diversity. CSD is considered to be the ancestral form of sex determination within the Hymenoptera because members of the most basal taxa have CSD while some of the more derived groups have other mechanisms of sex determination that produce the haplo-diploid pattern without penalizing inbreeding. In this study, we investigated sex determination in Heterospilus prosopidis Viereck, a parasitoid from a relatively primitive subfamily of the Braconidae, a hymenopteran family having species with and without CSD. By comparing sex ratio and mortality patterns produced by inbred and outbred females, we were able to rule out sl-CSD as a sex determination mechanism in this species. The absence of sl-CSD in H. prosopidis was unexpected given its basal phylogenetic position in the Braconidae. This and other recent studies suggest that sex determination systems in the Hymenoptera may be evolutionary labile. Heredity (2005) 95, 228-234.
A search for new dielectron mass resonances using data recorded by the CDF II detector and corres... more A search for new dielectron mass resonances using data recorded by the CDF II detector and corresponding to an integrated luminosity of 5.7 fb −1 is presented. No significant excess over the expected standard model prediction is observed. In this dataset, an event with the highest dielectron mass ever observed (960 GeV/c 2 ) was recorded. The results are interpreted in the Randall-Sundrum (RS) model. Combined with the 5.4 fb −1 diphoton analysis, the RS-graviton lower mass limit for the coupling k/M P l = 0.1 is 1058 GeV/c 2 , making it the strongest limit to date.
This letter reports a measurement of the top quark mass, Mtop, in data from pp collisions at √ s ... more This letter reports a measurement of the top quark mass, Mtop, in data from pp collisions at √ s = 1.96 TeV corresponding to 2.7 fb −1 of integrated luminosity at the Fermilab Tevatron using the CDF II detector. Events with the lepton+jets topology are selected. An unbinned likelihood is constructed based on the dependence of the lepton transverse momentum, PT, on Mtop. A maximum likelihood fit to the data yields a measured mass Mtop = 176.9 ± 8.0stat ± 2.7syst GeV/c 2 . In this measurement, the contribution by the jet energy scale uncertainty to the systematic error is negligible. The result provides an important consistency test for other Mtop measurements where explicit use of the jet energy is made for deriving the top quark mass. * Deceased † With visitors from
C-reactive protein (CRP), an inflammation marker, is a strong independent risk factor for cardiov... more C-reactive protein (CRP), an inflammation marker, is a strong independent risk factor for cardiovascular disease. Vessels are able to express CRP; however, the molecular mechanism behind this expression is not clear. Reverse transcription PCR and ELISA were used to detect messenger RNA and proteins of CRP and nuclear factor κB (NF-κB) activity in vessel rings stretched with different mechanical strains. Interleukin (IL)-6 treatment did not induce CRP expression in vessel rings of white rabbits in the absence of mechanical strain. In contrast, IL-6 augmented CRP expression in vessel rings stretched with mechanical strains of 3 and 5 g (CRP mRNA, IL-6: 11.367±1.68 and 12.78±0.76 vs vehicle: 7.27±0.88 and 8.3±0.91 folds, respectively; CRP, IL-6: 12.79±1.62 and 14.05±2.1 vs vehicle: 7.72±1.04 and 8.16±1.52 folds, respectively; p<0.05 vs 0 g group and vehicle control group; n=5), and this effect was completely blocked by treatment with gadolinium III chloride hexahydrate (GdCl3). Moreover, IL-6 treatment increased NF-κB activity in vessels stretched with a mechanical strain of 3 g, and this effect was blocked by stretch-activated channel inhibitors (streptomycin or GdCl3) and the NF-κB peptide inhibitor SN50, but not by the inactive SN50 analogue SN50M. We also performed similar experiments on human internal mammary arteries and obtained similar results. These results indicate that the inflammatory cytokine IL-6 alone does not induce CRP synthesis in vessels in the absence of mechanical strain; however, IL-6 augments mechanical strain-induced CRP synthesis in vessels via the stretch-activated channel-NF-κB pathway.
In the haplodiploid Hymenoptera, haploid males arise from unfertilized eggs, receiving a single s... more In the haplodiploid Hymenoptera, haploid males arise from unfertilized eggs, receiving a single set of maternal chromosomes while diploid females arise from fertilized eggs and receive both maternal and paternal chromosomes. Under single-locus complementary sex determination (sl-CSD), sex is determined by multiple alleles at a single locus. Sex locus heterozygotes develop as females, while hemizygous and homozygous eggs develop as haploid and diploid males, respectively. Diploid males, which are inviable or sterile in almost all cases studied, are therefore produced in high frequency under inbreeding or in populations with low sex allele diversity. CSD is considered to be the ancestral form of sex determination within the Hymenoptera because members of the most basal taxa have CSD while some of the more derived groups have other mechanisms of sex determination that produce the haplo-diploid pattern without penalizing inbreeding. In this study, we investigated sex determination in Heterospilus prosopidis Viereck, a parasitoid from a relatively primitive subfamily of the Braconidae, a hymenopteran family having species with and without CSD. By comparing sex ratio and mortality patterns produced by inbred and outbred females, we were able to rule out sl-CSD as a sex determination mechanism in this species. The absence of sl-CSD in H. prosopidis was unexpected given its basal phylogenetic position in the Braconidae. This and other recent studies suggest that sex determination systems in the Hymenoptera may be evolutionary labile. Heredity (2005) 95, 228-234.
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