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We propose a new method to measure various physical parameters, using characteristic weight functions. The method requires only lepton energy distribution and ideally it does not depend on the velocity of the parent particle. We demonstrate an application of this method by simulating a reconstruction of the Higgs boson mass in the H → WW → lνlν decaymodeattheLHC. Weshowthatsystematicerrorsaresuppressed compared to statistical errors. In the vector boson fusion channel, the statistical accuracy of the mass determination is estimated to be +12% and −14% at an integrated luminosity of 100 fb −1, assuming the Higgs boson mass to be 125 GeV and $ \sqrt{s} $ = 14 TeV. [ABSTRACT FROM AUTHOR]

We compare the perturbatively calculated QCD potential to that obtained from lattice calculations in the theory without light quark flavours. We examine Etot(r) = 2mpole +VQCD(r) by re-expressing it in the &Msmacr; mass &mmacr; = m&Msmacr; (m&Msmacr;) and by choosing specific prescriptions for fixing the scale μ (dependent on r and &mmacr;). By adjusting &mmacr; so as to maximise the range of convergence, we show that perturbative and lattice calculations agree up to 3 r0 ≈ 7.5 GeV-1 (r0 is the Sommer scale) within the uncertainty of order Λ QCD 3 r2. [ABSTRACT FROM AUTHOR]

We developed a new method for the full kinematical reconstruction of the tt system near its threshold at future linear e+e- colliders. In the core of the method lies likelihood fitting which is designed to improve measurement accuracies of the kinematical variables that specify the final states resulting from ti decays. The improvement is demonstrated by applying this method to a Monte Carlo tt sample generated with various experimental effects including beamstrahlung, finite acceptance and resolution of the detector system, etc. In most cases the fit takes a broad non-Gaussian distribution of a given kinematical variable to a nearly Gaussian shape, thereby justifying phenomenological analyses based on simple Gaussian smearing of the parton-level momenta. The standard deviations of the resultant distributions of various kinematical variables are given in order to facilitate such phenomenological analyses. A possible application of the kinematical fitting method and its expected impact are also discussed. [ABSTRACT FROM AUTHOR]

We investigated whether the measurement of serum interleukin 18 (IL-18) and intracellular cytokine analysis of peripheral blood CD4-positive T cells (ICA-CD4+ Tc) of chronic hepatitis C (CH-C) patients before and two weeks after interferon (IFN) administration are useful for predicting sustained response to IFN. Twenty-nine CH-C patients received IFN every day for two weeks and three times a week for 22 weeks. Patients were divided into two groups: responders, in whom serum HCV-RNA was undetectable at the end of the follow-up (week 48), and nonresponders, in whom any other patterns were seen. Before and two weeks after IFN administration, serum IL-18 and ICA-CD4+ Tc as described by Jung et al were measured. Serum IL-18 and the relative prevalence of IFN-gamma+ and IL-4+, IFN-gamma+ and IL-4 (Th-1), and IFN-gamma- and IL-4+ cells in the responders were significantly increased, but only the relative prevalence of Th-1 cells in the nonresponders was increased two weeks after IFN therapy. In conclusion, ICA-CD4+ Tc and the measurement of serum IL-18 might be useful for predicting IFN therapy by comparing the results between before and two weeks after IFN. [ABSTRACT FROM AUTHOR]

Using non-relativistic effective theories, new next-to-next-to-leading order (NNLO) QCD corrections to the total $$t{\bar t}$$ production cross section at the Linear Collider have been calculated recently. In this article the NNLO calculations of several groups are compared and the remaining uncertainties are discussed. The theoretical prospects for an accurate determination of top quark mass parameters are discussed in detail. An outlook on possible future improvements is given. [ABSTRACT FROM AUTHOR]

The Lysobacter lactamgenus YK90 pcbAB gene encoding δ-( l-α-aminoadipyl)- l-cysteinyl- d-valine (ACV) synthetase is located immediately upstream of the pcbC gene in the same orientation in the gene cluster involved in cephalosporin biosynthesis. The pcbAB gene encodes a large polypeptide composed of 3722 amino acid residues with a molecular mass of 411 593 Da. The predicted amino acid sequence has a high degree of similarity with those of known ACV synthetases from fungi and actinomycetes. Within the pcbAB amino acid sequence, three conserved and repeated domains of about 600 amino acids were identified. The domains also share a high degree of similarity with non-ribosomal peptide synthetases such as gramicidin synthatase 2 of Bacillus brevis. The pcbAB gene was expressed under the control of the lac promoter in Pseudomonas putida. Expression of the gene cluster involved in cephalosporin biosynthesis in P. putida led to the accumulation of β-lactam antibiotics. Deletion analysis of an open-reading frame located between the cefE and cefD genes from the gene cluster revealed that it encoded deacetylcephalosporin C synthetase ( cefF). From the results presented here and those of previous studies, the genes involved in cephalosporin biosynthesis in L. lactamgenus appear to be clustered in the order pcb AB-pcbC- cefE-cefF-cefD-bla in the same orientation within a 17-kb region of DNA. [ABSTRACT FROM AUTHOR]

Determination of the nucleotide sequence downstream from the Lysobacter lactamgenus pcbC gene encoding isopenicillin N synthase revealed that five open-reading frames (ORF) including the pcbC gene were tightly linked in the same orientation. Each ORF has the remarkable feature of the protein-coding frame in the DNA sequence with a high G + C content. Expression in Escherichia coli and a comparison of the deduced amino acid sequences with published sequences showed that the gene cluster contained a deacetoxycephalosporin C synthetase (DAOCS) gene (cefE), an ORF having homology with the Cephalosporium acremonium DAOCS/deacetylcephalosporin C synthetase gene (cefEF), an isopenicillin N epimerase gene( cefD), and a β-lactamase gene. The gene order was pcbC-cefE-ORF3- cefD-β-lactamase. [ABSTRACT FROM AUTHOR]

In a 68-year-old Japanese man, a gastric polyp 24mm in diameter with a stalk 15 mm in diameter was diagnosed as well differentiated adenocarcinoma and treated by endoscopic polypectomy. Histologically, most of the resected tissue was adenoma, and atypical cells were papillarily proliferating to form adenocarcinoma in adenoma, a Nakamura type IV gastric polyp. Infiltration of carcinoma was limited to within the mucosal layer. Immunohistochemical study with anti-CA19-9 antibody revealed positive staining in carcinoma cells. Serum CA19-9 level, which showed slight elevation, returned to the normal range 1 month after the polypectomy. The proliferating cell nuclear antigen (PCNA) labeling index and DNA ploidy pattern were analyzed in the resected tissue. The PCNA labeling index was 30% in carcinoma, 17% in adenoma, and 0.1% in the normal tissue. The DNA ploidy pattern was diploid in adenoma and aneuploid in adenocarcinoma. These findings suggest that gastric adenoma, as well as colonic adenoma, may have the potential for malignant transformation. [ABSTRACT FROM AUTHOR]

Koide's mass formula is an empirical relation among the charged lepton masses which holds with a striking precision. We present a model of charged lepton sector within an effective field theory with U(3) × SU(2) family gauge symmetry, which predicts Koide's formula within the present experimental accuracy. Radiative corrections as well as other corrections to Koide's mass formula have been taken into account. We adopt a known mechanism, through which the charged lepton spectrum is determined by the vacuum expectation value of a 9-component scalar field Φ. On the basis of this mechanism, we implement the following mechanisms into our model: (1) The radiative correction induced by family gauge interaction cancels the QED radiative correction to Koide's mass formula, assuming a scenario in which the U(3) family gauge symmetry and SU(2)L weak gauge symmetry are unified at 102–103 TeV scale; (2) A simple potential of Φ invariant under U(3) × SU(2) leads to a realistic charged lepton spectrum, consistent with the experimental values, assuming that Koide's formula is protected; (3) Koide's formula is stabilized by embedding U(3) × SU(2) symmetry in a larger symmetry group. Formally fine tuning of parameters in the model is circumvented (apart from two exceptions) by appropriately connecting the charged lepton spectrum to the boundary (initial) conditions of the model at the cut-off scale. We also disucss some phenomenological implications. [ABSTRACT FROM AUTHOR]

By facilitating a water/water phase separation (w/wPS), crowded biopolymers in cells form droplets that contribute to the spatial localization of biological components and their biochemical reactions. However, their influence on mechanical processes driven by protein motors has not been well studied. Here, we show that the w/wPS droplet spontaneously entraps kinesins as well as microtubules (MTs) and generates a micrometre-scale vortex flow inside the droplet. Active droplets with a size of 10-100 µm are generated through w/wPS of dextran and polyethylene glycol mixed with MTs, molecular-engineered chimeric four-headed kinesins and ATP after mechanical mixing. MTs and kinesin rapidly created contractile network accumulated at the interface of the droplet and gradually generated vortical flow, which can drive translational motion of a droplet. Our work reveals that the interface of w/wPS contributes not only to chemical processes but also produces mechanical motion by assembling species of protein motors in a functioning manner., (© 2023. The Author(s).)