759 research outputs found
Application of a mustard root bioassy to assess phytotoxicity of Group 2 herbicides
Non-Peer ReviewedGroup 2 herbicides exhibit high bioactivity at low concentrations in soil and may persist into the next growing season causing crop injury. A bioassay that is suitable for the detection of a range of Group 2 herbicides was developed; in this bioassay, a root growth inhibition of oriental mustard is used for the determination of the herbicide concentration in soil. The Group 2 herbicides included were: Everest (flucarbazone-sodium), Frontline (florasulam), Sundance (sulfosulfuron), and Odyssey (imazamox + imazethapyr). This bioassay was used to examine the degree of root inhibition by simultaneous application of two Group 2 herbicides. Application of varying levels of flucarbazone or sulfosulfuron combined with Odyssey resulted in root length inhibition that was comparable to the root length inhibition caused by application of flucarbazone alone or sulfosulfuron alone and Odyssey alone, possibly indicating an additive
effect of these pairs of herbicides. Further studies are needed to examine which combinations of Group 2 herbicides under what environmental and soil conditions may result in âstackingâ causing increased plant injury
Quartic Anomalous Couplings in Colliders
We study the constraints on the vertices ,
, and that can be obtained from
triple-gauge-boson production at the next generation of linear
colliders operating in the mode. We analyze the processes
(, or ) and show that these reactions
increase the potential of machines to search for anomalous
four-gauge-boson interactions.Comment: 15 pages, Latex file using ReVteX, 4 uufiled figures include
Environment-wide association study to comprehensively test and validate associations between nutrition and lifestyle factors and testosterone deficiency: NHANES 1988-1994 and 1999-2004
PURPOSE
Testosterone (T) plays an important role in men's health and its deficiency is linked with poorer health. However, the role of nutritional and lifestyle factors in T regulation and production remains unclear. The objectives are to comprehensively test the cross-sectional associations of nutritional and lifestyle factors with T deficiency and to validate the associations in the NHANES survey.
METHODS
We performed weighted multivariable logistic regression analysis to examine the association of 173 nutritional and lifestyle factors with T deficiency (total testosterone â€â3.5 ng/mL) in NHANES III as the discovery set (mean age 41). We controlled for multiple comparisons with a false discovery rate (FDR)â<â5% and replicated in NHANES 1999-2004 (mean age 44).
RESULTS
We identified seven nutritional factors as being inversely associated with T deficiency in NHANES 1999-2004, namely dietary intake of vitamin A, protein, saturated fatty acids, monounsaturated fatty acids, total fats, saturated fatty acid 16:0, and phosphorus. In a multivariable model, only vitamin A intake remained significantly associated with T deficiency (OR 0.97, 95% CI 0.94-0.99). Principal component analysis suggested that the two principal components, (1) dietary fats, protein, and phosphorous and (2) total vitamin A, may be associated with T deficiency.
CONCLUSION
Our systematic evaluation provided new insight into the modifiable factors that could play a role in the regulation of T production. This study has the potential to contribute to the current body of literature which seeks to formulate a clinical definition of T deficiency after taking into account nutritional and lifestyle factors
Physics at the Linear Collider
The physics at the planned colliders is discussed around three main
topics corresponding to different manifestations of symmetry breaking:
physics in the no Higgs scenario, studies of the properties of the Higgs and
precision tests of SUSY. A comparison with the LHC is made for all these cases.
The mode of the linear collider will also be reviewed.Comment: 31 pages, 12 figures. Invited talk given at the Fifth Workshop on
High Energy Physics Phenomenology, Inter-University Centre for Astronomy and
Astrophysics, Pune, India, January 12 - 26, 199
Prevalence Rates of Mental Disorders in Chilean Prisons
PMCID: PMC371883
The visible effect of a very heavy magnetic monopole at colliders
If a heavy Dirac monopole exists, the light-to-light scattering below the
monopole production threshold is enhanced due to strong coupling of monopoles
to photons. At the next Linear Collider with electron beam energy 250 GeV this
photon pair production could be observable at monopole masses less than 2.5-6.4
TeV in the mode or 3.7-10 TeV in the mode, depending on
the monopole spin. At the upgraded Tevatron such an effect is expected to be
visible at monopole masses below 1-2.5 TeV. The strong dependence on the
initial photon polarizations allows to find the monopole spin in experiments at
and colliders. We consider the production and
the production at and or colliders via the
same monopole loop. The possibility to discover these processes is
significantly lower than that of the case.Comment: 18 pages, 2 figures, RevTe
Radiative production of invisible charginos in photon photon collision
If in a supersymmetric model, the lightest chargino is nearly degenerate with
the lightest neutralino, the former can decay into the latter alongwith a soft
pion (or a lepton-neutrino pair). Near degeneracy of the chargino and
neutralino masses can cause the other decay products (the pion or the lepton)
to be almost invisible. Photon-photon colliders offer a possibility of clean
detection of such an event through a hard photon tag.Comment: 12 pages, 5 postscript figure
The Higgs - photon - Z boson coupling revisited
We analyze the coupling of CP-even and CP-odd Higgs bosons to a photon and a
Z boson in extensions of the Standard Model. In particular, we study in detail
the effect of charged Higgs bosons in two-Higgs doublet models, and the
contribution of SUSY particle loops in the minimal supersymmetric extension of
the Standard Model. The Higgs- coupling can be measured in the decay
+Higgs at colliders running on the Z resonance, or in
the reverse process Higgs with the Higgs boson produced at LHC.
We show that a measurement of this coupling with a precision at the percent
level, which could be the case at future colliders, would allow to
distinguish between the lightest SUSY and standard Higgs bosons in large areas
of the parameter space.Comment: 18 pages LaTex + 7 figures (ps). Typo corrected in eq.(5
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Callous-unemotional traits, low cortisol reactivity and physical aggression in children: findings from the Wirral Child Health and Development Study
Callous-unemotional (CU) traits are thought to confer risk for aggression via reduced amygdala responsivity to distress cues in others. Low cortisol reactivity is thought to confer risk for aggression via reduced arousal and this effect may be confined to boys. We tested the hypothesis that the association between childhood CU traits and aggression would be greatest in the absence of the inhibitory effects of cortisol reactivity, and that this effect would be sex dependent. Participants were 283 members of a stratified subsample within an epidemiological longitudinal cohort (WCHADS). Cortisol reactivity to a social stressor was assessed at 5 years. CU traits were reported by mothers at 5 years, and physical aggression by mothers and teachers at age 7. Results showed that CU traits were associated with elevated aggression at 7 years controlling for earlier aggression. There was no main effect of cortisol reactivity on regression. The association between CU traits and aggression was moderated by cortisol reactivity (pâ=â.011) with a strong association between CU traits and aggression in the presence of low reactivity, and a small and non-significant association in the presence of high reactivity. This association was further moderated by child sex (pâ=â.041) with the joint effect of high CU traits and low cortisol reactivity seen only in boys (pâ=â.016). We report first evidence that a combined deficit in inhibitory processes associated with CU traits and low cortisol reactivity increases risk for childhood aggression, in a sex-dependent manner
Detecting and Studying Higgs Bosons at a Photon-Photon Collider
We examine the potential for detecting and studying Higgs bosons at a
photon-photon collider facility associated with a future linear collider. Our
study incorporates realistic \gam\gam luminosity spectra based on the most
probable available laser technology. Results include detector simulations. We
study the cases of: a) a SM-like Higgs boson; b) the heavy MSSM Higgs bosons;
c) a Higgs boson with no couplings from a general two Higgs doublet
model.Comment: 52 pages, 26 figures, revised version with new appendi
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