214 research outputs found
NNI-Form Quark Mass Matrix Expressed by the Observable Quantities
It is pointed out that the phase convention of the CKM matrix V affects
texture analysis of the quark mass matrices (M_u, M_d) when we try to describe
(M_u, M_d) by the observable quantities (quark masses and CKM matrix
parameters) only. This is demonstrated for a case of the non-Hermitian
Fritzsch-type mass matrix (tilde{M}_u, tilde{M}_d), which is a general
expression of quark mass matrix (M_u, M_d) and is described by twelve
parameters. We find that we can always choose a phase convention of V which
yields tilde{M}_{u32} = 0, so that the remaining ten parameters in (tilde{M}_u,
tilde{M}_d) can completely be expressed by the ten observable quantities.Comment: 11 pages (LaTeX); Title was change
Eta-Helium Quasi-Bound States
The cross section and tensor analysing power t_20 of the d\vec{d}->eta 4He
reaction have been measured at six c.m. momenta, 10 < p(eta) < 90 MeV/c. The
threshold value of t_20 is consistent with 1/\sqrt{2}, which follows from
parity conservation and Bose symmetry. The much slower momentum variation
observed for the reaction amplitude, as compared to that for the analogous
pd->eta 3He case, suggests strongly the existence of a quasi-bound state in the
eta-4He system and optical model fits indicate that this probably also the case
for eta-3He.Comment: LaTeX, uses elsart.sty, 10 pages, 3 Postscript figures, Submitted to
Physics Letters
Which Kubo formula gives the exact conductance of a mesoscopic disordered system?
In both research and textbook literature one often finds two ``different''
Kubo formulas for the zero-temperature conductance of a non-interacting Fermi
system. They contain a trace of the product of velocity operators and
single-particle (retarded and advanced) Green operators: or . The study investigates the relationship between
these expressions, as well as the requirements of current conservation, through
exact evaluation of such quantum-mechanical traces for a nanoscale (containing
1000 atoms) mesoscopic disordered conductor. The traces are computed in the
semiclassical regime (where disorder is weak) and, more importantly, in the
nonperturbative transport regime (including the region around
localization-delocalization transition) where concept of mean free path ceases
to exist. Since quantum interference effects for such strong disorder are not
amenable to diagrammatic or nonlinear -model techniques, the evolution
of different Green function terms with disorder strength provides novel insight
into the development of an Anderson localized phase.Comment: 7 pages, 5 embedded EPS figures, final published version (note: PRB
article has different title due to editorial censorship
Sex differences in the association between dynapenic abdominal obesity and onset of disability in activities of daily living among adults aged ≥50 years: A prospective analysis of the Irish Longitudinal Study on Ageing
Background: Sex differences in the longitudinal relationship between dynapenic abdominal obesity, i.e., impairment in muscle strength and high waist circumference, and disability in activities of daily living have not been investigated to date. Therefore, we aimed to examine sex differences in the longitudinal association between dynapenic abdominal obesity at baseline and the onset of disability in activities of daily living during a four-year follow-up period among Irish adults aged ≥50 years. Methods: Data from Wave 1 (2009–2011) and Wave 3 (2014–2015) of the Irish Longitudinal Study on Ageing survey were analyzed. Dynapenia was defined as handgrip strength of <26 kg for men and <16 kg for women. Abdominal obesity was defined as waist circumference of >88 cm for women and >102 cm for men. Dynapenic abdominal obesity was defined as having both dynapenia and abdominal obesity. Disability was defined as having difficulty with at least one of six activities of daily living (dressing, walking, bathing, eating, getting in or out of bed, using the toilet). Multivariable logistic regression was conducted to assess associations. Results: Data on 4471 individuals aged ≥50 years and free of disability at baseline were analyzed [mean (SD) age 62.3 (8.6) years; 48.3 % males]. In the overall sample, compared to no dynapenia and no abdominal obesity, dynapenic abdominal obesity was associated with 2.15 (95%CI = 1.17–3.93) times higher odds for incident disability at 4-year follow-up. This association was significant among men (OR = 3.78; 95%CI = 1.70–8.38) but not among women (OR = 1.34; 95%CI = 0.60–2.98). Conclusions: Interventions to prevent or address dynapenic abdominal obesity may aid in the prevention of disability, especially among men
Marital status and mortality among Japanese men and women: the Japan Collaborative Cohort Study
<p>Abstract</p> <p>Background</p> <p>Several studies have indicated a significant association between marital status and mortality risks. However, most of these studies have compared married and unmarried people without differentiating among single, divorced and widowed status. Moreover, gender differences in mortality rates associated with marital status have not been sufficiently clarified. With significant increases in the percentages of divorced and widowed people and a corresponding drop in the marriage rate in Japan during the past two or three decades, it can be expected that these changes will have a significant impact on mortality rates.</p> <p>Methods</p> <p>This investigation used a prospective study of a total of 94,062 Japanese men and women aged 40–79 who completed self-administered questionnaires at baseline and during a followed-up of 9.9-years.</p> <p>Results</p> <p>Compared with married men, never-married men showed higher risks of mortality from cardiovascular disease [relative risk (RR) = 3.05, 95% confidence interval (CI) 2.03–4.60], respiratory disease (RR = 2.43, 95%CI 1.27–4.63), external causes (RR = 2.18, 95%CI 1.05–4.54) and all causes (RR = 1.91, 95%CI 1.51–2.42) after adjustment for potentially confounding variables. For never-married women, there was a smaller but significantly higher risk of mortality from all causes (RR = 1.46, 95%CI 1.15–1.84). Divorced and widowed men showed moderately higher risks of mortality from cardiovascular disease, external causes and all causes compared with married men, but such a trend was not observed in women.</p> <p>Conclusion</p> <p>Single status was associated with a higher risk of mortality than was married status for both men and women. Divorce and widowhood were associated with elevated risk for men, but not for women. These findings suggest single, divorce and widowhood status constitute potentially adverse health effects.</p
Stiff monatomic gold wires with a spinning zigzag geometry
Using first principles density functional calculations, gold monatomic wires
are found to exhibit a zigzag shape which remains under tension, becoming
linear just before breaking. At room temperature they are found to spin, what
explains the extremely long apparent interatomic distances shown by electron
microscopy.The zigzag structure is stable if the tension is relieved, the wire
holding its chainlike shape even as a free-standing cluster. This unexpected
metallic-wire stiffness stems from the transverse quantization in the wire, as
shown in a simple free electron model.Comment: 4 pages, latex, 5 figures, submitted to PR
Competitiveness and communication for effective inoculation byRhizobium, Bradyrhizobium and vesicular-arbuscular mycorrhiza fungi
After a short summary on the ecology and rhizosphere biology of symbiotic bacteria and vesicular-arbuscular (VA) mycorrhiza fungi and their application as microbial inocula, results on competitiveness and communication are summarized. Stress factors such as high temperature, low soil pH, aluminium concentrations and phytoalexins produced by the host plants were studied withRhizobium leguminosarum bv.phaseoli andRhizobium tropici onPhaseolus beans. Quantitative data for competitiveness were obtained by usinggus + (glucoronidase) labelled strains, which produce blue-coloured nodules. ForPhaseolus-nodulating rhizobia, a group specific DNA probe was also developed, which did not hybridize with more than 20 other common soil and rhizosphere bacteria. Results from several laboratories contributing to knowledge of signal exchange and communication in theRhizobium/Bradyrhizobium legume system are summarized in a new scheme, including also defense reactions at the early stages of legume nodule initiation. Stimulating effects of flavonoids on germination and growth of VA mycorrhiza fungi were also found. A constitutive antifungal compound in pea roots, -isoxazolinonyl-alanine, was characterized
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New Faces and New Masks of Today's Consumer
In 1995, we proposed that consumption and contemporary consumerism could not be studied or understood separately from the world of work and production. We proposed that contemporary consumerism was built on the back of what we referred to as `the Fordist Deal'. This deal, pioneered by Henry Ford for his employees, was the promise of ever increasing standards of living in exchange for a quiescent labour force accepting alienating work. Since that deal was struck, consumerism came to signify a general pre-occupation with consumption standards and choice as well as a willingness to read meanings in material commodities and to equate happiness and success with material possessions. In this sense, Ford may be seen as the father both of mass production and mass consumption. Since the Fordist high noon of consumerism in the West, mass consumption is widely seen as having fragmented into a proliferation of highly individualized niche products. For its part, a considerable part of mass production has migrated to countries with lower wages and looser environmental and social controls, fueling their own variants of consumerism. In this article, we examine the gradual erosion of the Fordist Deal in the light of developments in the last 10 years or so, seeking to assess the future of consumerism at a global level. We also seek to identify and discuss some emerging conceptualizations of the consumer, some of the new faces and masks assumed by the archetypal character of our types. We analyse some of the tensions and contradictions lurking behind these conceptualizations and try to envisage some of the real choices facing consumers today and some of the processes of social change that hinge on the outcomes of these choices. The article identifies a fundamental paradox between the ubiquity of the consumer in contemporary discourses and the virtual impossibility of generalizing about consumers. We suggest, then, that the consumer may be viewed as one of those `essentially contested concepts' proposed by Gallie that defy domestication. The consumer, we argue, is unmanageable, both as a concept, since no-one can pin it down to one specific conceptualization at the expense of all others, and as an entity, since attempts to control and manage the consumer lead to the consumer mutating from one impersonation to another. It is precisely this paradox that we seek to capture in our article's title. The article concludes with a consideration of three basic challenges that are liable to lead to fundamental reorientation of consumption and production, as well as of our conceptualizations and theorizing about them. These challenges are the outcomes of environmental, demographic and social factors that, we argue, make the current situation unsustainable and will bring about its dissolution
Light Scalar Top and Heavy Top Signature at CDF
We propose a mechanism which could explain a slight excess of top signal rate
recently reported by CDF in the framework of the supersymmetric standard model.
If the scalar partner of the top (stop) is sufficiently light, the gluino with
an appropriate mass could decay into the stop plus the top with almost 100\%
branching ratio and experimental signatures of the gluino pair production could
be indistinguishable from those of the top production in the present integrated
luminosity Tevatron running. In this case the standard top signal,
multi-jets events, would be effectively enhanced by the additional gluino
contribution. It is shown, moreover, that such a mechanism can actually work in
the radiative SU(2)U(1) breaking model without the GUT relations
between the gaugino mass parameters.Comment: 8 pages (LaTeX), 3 figures not included (available on request) ;
ITP-SU-94/03, RUP-94-0
The IceCube Neutrino Observatory: Instrumentation and Online Systems
The IceCube Neutrino Observatory is a cubic-kilometer-scale high-energy
neutrino detector built into the ice at the South Pole. Construction of
IceCube, the largest neutrino detector built to date, was completed in 2011 and
enabled the discovery of high-energy astrophysical neutrinos. We describe here
the design, production, and calibration of the IceCube digital optical module
(DOM), the cable systems, computing hardware, and our methodology for drilling
and deployment. We also describe the online triggering and data filtering
systems that select candidate neutrino and cosmic ray events for analysis. Due
to a rigorous pre-deployment protocol, 98.4% of the DOMs in the deep ice are
operating and collecting data. IceCube routinely achieves a detector uptime of
99% by emphasizing software stability and monitoring. Detector operations have
been stable since construction was completed, and the detector is expected to
operate at least until the end of the next decade.Comment: 83 pages, 50 figures; updated with minor changes from journal review
and proofin
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