2,101 research outputs found
Governance, Deterrence, and National Homicide Rate
By extending the deterrence theory to national level the current study tested the hypothesis that ineffective government is largely responsible for higher homicide rate in a nation The homicide data required for the test were collected from the World Health Organization and the information on governance from the World Bank s World Governance Indicators for 122 nations The results from the regression models supported the deterrence theory An ineffective and dysfunctional government was one of the primary sources for a nation s high homicide rate Also other control variables such as relative poverty and ethnic heterogeneity were positively related to the homicide rate in a natio
The stransverse mass, MT2, in special cases
This document describes some special cases in which the stransverse mass,
MT2, may be calculated by non-iterative algorithms. The most notable special
case is that in which the visible particles and the hypothesised invisible
particles are massless -- a situation relevant to its current usage in the
Large Hadron Collider as a discovery variable, and a situation for which no
analytic answer was previously known. We also derive an expression for MT2 in
another set of new (though arguably less interesting) special cases in which
the missing transverse momentum must point parallel or anti parallel to the
visible momentum sum. In addition, we find new derivations for already known
MT2 solutions in a manner that maintains manifest contralinear boost invariance
throughout, providing new insights into old results. Along the way, we stumble
across some unexpected results and make conjectures relating to geometric forms
of M_eff and H_T and their relationship to MT2.Comment: 11 pages, no figures. v2 corrects minor typos. v3 corrects an
incorrect statement in footnote 8 and inserts a missing term in eq (3.9). v4
and v5 correct minor typos spotted by reader
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Compensation of atmospheric CO2 buildup through engineered chemical shrinkage
Retrieval of background carbon dioxide into regional chemical extractors would counter anthropogenic inputs in a manner friendly to established industries. We demonstrate via atmospheric transport/scaling calculations that for idealized flat removal units, global coverage could be less than two hundred thousand square kilometers. The disrupted area drops to a small fraction of this with engineering into the vertical to bypass laminarity. Fence structures and artificial roughness elements can both be conceived. Sink thermodynamics are analyzed by taking calcium hydroxide as a sample reactant. Energy costs could be minimized at near the endothermicity of binding reversal. In the calcium case the value is 25 kcal mole-1, as against a fuel carbon content of 150 in the same units. Aqueous kinetics are less than favorable for the hydroxide, but misting could counteract slow liquid phase transfer. Properties of superior scrubbers are outlined
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Chemical transport modeling of potential atmospheric CO2 sinks
The potential for carbon dioxide (CO2) sequestration via engineered chemical sinks is investigated using a three dimensional chemical transport model (CTM). Meteorological and chemical constraints for flat or vertical systems that would absorb CO2 from the atmosphere, as well as an example chemical system of calcium hydroxide (Ca(OH)2) proposed by Elliott et al. [Compensation of atmospheric CO2 buildup through engineered chemical sinkage, Geophys. Res. Lett. 28 (2001) 1235] are reviewed. The CTM examines land based deposition sinks, with 4° × 5° latitude/longitude resolution at various locations, and deposition velocities (v). A maximum uptake of ∼20 Gton (1015 g) Cyr-1 is attainable with v ≥ 5 cms-1 at a mid-latitude site. The atmospheric increase of CO2 (3 Gtonyr-1) can be balanced by an engineered sink with an area of no more than 75, 000 km2 at v of 1 cms-1. By building the sink upwards or splitting this area into narrow elements can reduce the active area by more than an order of magnitude as discussed in Dubey et al. © 2002 Elsevier Science Ltd. All rights reserved
Supersymmetric particle mass measurement with the boost-corrected contransverse mass
A modification to the contransverse mass (MCT) technique for measuring the
masses of pair-produced semi-invisibly decaying heavy particles is proposed in
which MCT is corrected for non-zero boosts of the centre-of-momentum (CoM)
frame of the heavy states in the laboratory transverse plane. Lack of knowledge
of the mass of the CoM frame prevents exact correction for this boost, however
it is shown that a conservative correction can nevertheless be derived which
always generates an MCT value which is less than or equal to the true value of
MCT in the CoM frame. The new technique is demonstrated with case studies of
mass measurement with fully leptonic ttbar events and with SUSY events
possessing a similar final state.Comment: 33 pages, 33 .eps figures, JHEP3 styl
ATTITUDES AND THE PRACTICE OF DOCUMENTATION OF INDIGENOUS KNOWLEDGE BY THE TRADITIONAL HEALTH PRACTITIONERS IN KWARA STATE, NIGERIA.
This paper examines the attitudes and the practice of documentation of indigenous knowledge by the traditional health practitioners (THP) in Kwara State, Nigeria. Indigenous knowledge has been playing significant roles most especially in the primary health of the people in rural areas. This important knowledge is prone to attrition due to non-documentation and the World Bank has warned that if the knowledge is not documented, it will be lost. The study adopted descriptive survey research design and utilized questionnaire to collect data for the study. 30 traditional health practitioners were purposively selected based on their experience for the study. Simple percentage and frequency count were used to analyse the biographic variables while the research questions were answered using means and standard deviation while the hypotheses were tested using Pearson Correlation. The result of the study shows that there were more male traditional health practitioners than female, the higher percentage of them were elderly and highly experienced in the practice. The practitioners had positive attitudes to documentation of their IK and there is significant relationship between attitudes and documentation of IK. Writing and storytelling are the most prominent practice of documentation and that lock of formal education, fear of loss of ownership of the knowledge, misuse of the documented knowledge among others are challenges facing documentation of Ik in Kwara State, Nigeria. The study concludes that THP should be helped to overcome these challenges so that they will be encouraged to document their IK to prevent it from going into extinction
Reducing combinatorial uncertainties: A new technique based on MT2 variables
We propose a new method to resolve combinatorial ambiguities in hadron
collider events involving two invisible particles in the final state. This
method is based on the kinematic variable MT2 and on the MT2-assisted-on-shell
reconstruction of invisible momenta, that are reformulated as `test' variables
Ti of the correct combination against the incorrect ones. We show how the
efficiency of the single Ti in providing the correct answer can be
systematically improved by combining the different Ti and/or by introducing
cuts on suitable, combination-insensitive kinematic variables. We illustrate
our whole approach in the specific example of top anti-top production, followed
by a leptonic decay of the W on both sides. However, by construction, our
method is also directly applicable to many topologies of interest for new
physics, in particular events producing a pair of undetected particles, that
are potential dark-matter candidates. We finally emphasize that our method is
apt to several generalizations, that we outline in the last sections of the
paper.Comment: 1+23 pages, 8 figures. Main changes in v3: (1) discussion at the end
of sec. 2 improved; (2) added sec. 4.2 about the method's dependence on mass
information. Matches journal versio
Sqrt{shat}_{min} resurrected
We discuss the use of the variable sqrt{shat}_{min}, which has been proposed
in order to measure the hard scale of a multi parton final state event using
inclusive quantities only, on a SUSY data sample for a 14 TeV LHC. In its
original version, where this variable was proposed on calorimeter level, the
direct correlation to the hard scattering scale does not survive when effects
from soft physics are taken into account. We here show that when using
reconstructed objects instead of calorimeter energy and momenta as input, we
manage to actually recover this correlation for the parameter point considered
here. We furthermore discuss the effect of including W + jets and t tbar+jets
background in our analysis and the use of sqrt{shat}_{min} for the suppression
of SM induced background in new physics searches.Comment: 23 pages, 9 figures; v2: 1 figure, several subsections and references
as well as new author affiliation added. Corresponds to published versio
General analysis of signals with two leptons and missing energy at the Large Hadron Collider
A signal of two leptons and missing energy is challenging to analyze at the
Large Hadron Collider (LHC) since it offers only few kinematical handles. This
signature generally arises from pair production of heavy charged particles
which each decay into a lepton and a weakly interacting stable particle. Here
this class of processes is analyzed with minimal model assumptions by
considering all possible combinations of spin 0, 1/2 or 1, and of weak
iso-singlets, -doublets or -triplets for the new particles. Adding to existing
work on mass and spin measurements, two new variables for spin determination
and an asymmetry for the determination of the couplings of the new particles
are introduced. It is shown that these observables allow one to independently
determine the spin and the couplings of the new particles, except for a few
cases that turn out to be indistinguishable at the LHC. These findings are
corroborated by results of an alternative analysis strategy based on an
automated likelihood test.Comment: 18 pages, 3 figures, LaTe
Peer support for people with personality disorder: A 6-session peer and clinician co-facilitated group program – Participant Workbook
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