881 research outputs found
The Characteristics of Necessity, Commoner, and Parasite with Multicultural Data Comparison
Three different types of employees can be found in workplaces all over the world: “Necessities,” “Commoners,” and “Parasites.” A person is a Necessity if s/he is irreplaceable and crucial to the functioning of an organization. A Commoner is a person of normal ability and talent who has no significant impact on organizational success. Parasites are detrimental freeloaders who damage the functioning of an organization. To identify the principal characteristics of these three types of workers, a group of researchers led by Chong W. Kim conducted six studies in which they collected survey data from undergraduate and graduate business students in the U.S., India, Korea, Chile, and Japan. The results of this research effort are reported in Kim & Sikula (2005), Kim & Sikula (2006), Kim, Sikula & Smith (2006), Kim, Cho & Sikula (2007), Kim, Arias- Bolzmann & Smith (2008), and Kim, Arias-Bolzmann & Magoshi (2009). The summary of these six studies has been reported in Kim, Smith, Sikula & Anderson (2011). The purpose of this article is to compare the results of the summary study with a new set of data, which was collected from a multicultural student body. The authors note the points of commonality between the data sets and offer their thoughts on future research in this area
Singlet Fermionic Dark Matter with Dark
We present a fermionic dark matter model mediated by the hidden gauge boson.
We assume the QED-like hidden sector which consists of a Dirac fermion and
U(1) gauge symmetry, and introduce an additional scalar electroweak doublet
field with the U(1) charge as a mediator. The hidden U(1) symmetry is
spontaneously broken by the electroweak symmetry breaking and there exists a
massive extra neutral gauge boson in this model which is the mediator between
the hidden and visible sectors. Due to the U(1) charge, the additional
scalar doublet does not couple to the Standard Model fermions, which leads to
the Higgs sector of type I two Higgs doublet model. The new gauge boson couples
to the Standard Model fermions with couplings proportional to those of the
ordinary boson but very suppressed, thus we call it the dark boson. We
study the phenomenology of the dark boson and the Higgs sector, and show
the hidden fermion can be the dark matter candidate.Comment: 10 pages, 3 figure
Phenomenology of a two-component dark matter model
We study a two-component dark matter model consisting of a Dirac fermion and
a complex scalar charged under new U(1) gauge group in the hidden sector. The
dark fermion plays the dominant component of dark matter which explains the
measured DM relic density of the Universe. It has no direct coupling to
ordinary standard model particles, thus evading strong constraints from the
direct DM detection experiments. The dark fermion is self-interacting through
the light dark gauge boson and it would be possible to address that this model
can be a resolution to the small scale structure problem of the Universe. The
light dark gauge boson, which interacts with the standard model sector, is also
stable and composes the subdominant DM component. We investigate the model
parameter space allowed by current experimental constraints and
phenomenological bounds. We also discuss the sensitivity of future experiments
such as SHiP, DUNE and ILC, for the obtained allowed parameter space.Comment: 13 pages, 1 figure, journal versio
Structural dynamics and divergence of the polygalacturonase gene family in land plants
A distinct feature of eukaryotic genomes is the presence of gene families. The polygalacturonase (PG) (EC3.2.1.15) gene family is one of the largest gene families in plants. PG is a pectin-digesting enzyme with a glycoside hydrolase 28 domain. It is involved in numerous plant developmental processes. The evolutionary processes accounting for the functional divergence and the specialized functions of PGs in land plants are unclear. Here, phylogenetic and gene structure analysis of PG genes in algae and land plants revealed that land plant PG genes resulted from differential intron gain and loss, with the latter event predominating. PG genes in land plants contained 15 homologous intron blocks and 13 novel intron blocks. Intron position and phase were not conserved between PGs of algae and land plants but conserved among PG genes of land plants from moss to vascular plants, indicating that the current introns in the PGs in land plants appeared after the split between unicellular algae and multicelluar land plants. These findings demonstrate that the functional divergence and differentiation of PGs in land plants is attributable to intronic loss. Moreover, they underscore the importance of intron gain and loss in genomic adaptation to selective pressure
Vacuum stability of conformally invariant scalar dark matter models
We discuss vacuum structure and vacuum stability in classically
scale-invariant renormalizable models with a scalar dark matter multiplet of
global O(N) symmetry together with an electroweak singlet scalar mediator. Our
conformally invariant scalar potential generates the electroweak symmetry
breaking via the Coleman-Weinberg mechanism, and the new scalar singlet
mediator acquires its mass through radiative corrections of the scalar dark
matters as well as of the standard model particles. Taking into account the
present collider bounds, we find the region of parameter space where the scalar
potential is stable and all the massless couplings are perturbative up to the
Planck scale. With the obtained parameter sets satisfying the vacuum stability
condition, we present the allowed region of new physics parameters satisfying
the recent measurement of relic abundance, and predict the elastic scattering
cross section of the new scalar multiplet into target nuclei for a direct
detection of the dark matter. We also discuss the collider signatures and
future discovery potentials of the new scalars.Comment: 11 pages, 6 figures (partly updated), journal version. arXiv admin
note: text overlap with arXiv:1904.1020
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