1,158 research outputs found
Turning up by turning over : the change of scenery effect in major league baseball
Purpose: This study examined a “change of scenery” effect on performance in major league baseball (MLB). We also tested this effect for voluntary versus involuntary employee departures, as well as employees returning to a past employer.
Design/Methodology/Approach: This study uses publicly available MLB performance data from 2004 to 2015. The data comprise 712 team changes for players following two consecutive years with the same organization. Data were analyzed using MANCOVA to assess the impact of changing teams on player performance.
Findings: Results indicate players with declining performance benefited significantly from a change of scenery. Following a team change, these players experienced a significant increase in their performance that remained stable through a subsequent season. The effect was not different for players who changed teams via trade and free agency and was modest for those returning to a past organization. Analysis also showed that players leaving while their performance was improving suffered a subsequent performance drop-off in the new organization.
Implications: As the war for talent escalates and employees change jobs more frequently, extending our understanding of how performance can be influenced by work context may provide new insight into organization staffing policies.
Originality/Value: Results extend field theory by highlighting how past performance interacts with new work contexts to influence performance. This is one of the few studies evaluating the job change-performance relationship, and perhaps the first to account for the effects of performance trends prior to exit
Adiabatic scaling relations of galaxy clusters
The aim of the present work is to show that, contrary to popular belief,
galaxy clusters are **not** expected to be self-similar, even when the only
energy sources available are gravity and shock-wave heating. In particular, we
investigate the scaling relations between mass, luminosity and temperature of
galaxy groups and clusters in the absence of radiative processes. Theoretical
expectations are derived from a polytropic model of the intracluster medium and
compared with the results of high-resolution adiabatic gasdynamical
simulations. It is shown that, in addition to the well-known relation between
the mass and concentration of the dark matter halo, the effective polytropic
index of the gas also varies systematically with cluster mass, and therefore
neither the dark matter nor the gas profiles are exactly self-similar. It is
remarkable, though, that the effects of concentration and polytropic index tend
to cancel each other, leading to scaling relations whose logarithmic slopes
roughly match the predictions of the most basic self-similar models. We provide
a phenomenological fit to the relation between polytropic index and
concentration, as well as a self-consistent scheme to derive the non-linear
scaling relations expected for any cosmology and the best-fit normalizations of
the M-T, L-T and F-T relations appropriate for a Lambda-CDM universe. The
predicted scaling relations reproduce observational data reasonably well for
massive clusters, where the effects of cooling and star formation are expected
to play a minor role.Comment: 12 pages, 5 figures, accepted by MNRA
Social comparisons and organizational support : implications for commitment and retention
Organizational support theory (OST) suggests that employees develop a general perception of the extent to which the organization values their contributions and cares about their well-being (perceived organizational support – POS), and respond to that support through attitudes and behaviors that are beneficial toward the organization. Although OST emphasizes both social exchange and self-enhancement processes, most accounts of POS’s effects are rooted in social exchange. For example, POS’s linkages with commitment and retention have been explained as an exchange of support for positive attitudes and continued employment. This research sheds light on self-enhancement’s less-understood role in fostering these reactions by demonstrating the influence of social comparison effects. Drawing on a sample of 342 employees nested in 82 work-units of a US hospitality company, our analysis demonstrates that favorable POS comparisons with peers in one’s work-unit are positively associated with commitment and retention, whereas unfavorable comparisons are negatively related. Results also show that comparisons taking place in less-supported work-units have stronger impact than comparisons made in those with better support. Our findings extend OST by revealing the importance of social comparisons in engendering responses to organizational support, and in so doing potentially explicate the differential ways social exchange and self-enhancement operate with regard to POS
Phase 1b/2a trial of the superoxide dismutase mimetic GC4419 to reduce chemoradiotherapy-induced oral mucositis in patients with oral cavity or oropharyngeal carcinoma
PURPOSE: To assess the safety of the superoxide dismutase mimetic GC4419 in combination with radiation and concurrent cisplatin for patients with oral cavity or oropharyngeal cancer (OCC) and to assess the potential of GC4419 to reduce severe oral mucositis (OM).
PATIENTS AND METHODS: Patients with locally advanced OCC treated with definitive or postoperative intensity modulated radiation therapy (IMRT) plus cisplatin received GC4419 by 60-minute intravenous infusion, ending \u3c60 minutes before IMRT, Monday through Friday for 3 to 7 weeks, in a dose and duration escalation study. Oral mucositis was assessed twice weekly during and weekly after IMRT.
RESULTS: A total of 46 patients received GC4419 in 11 separate dosing and duration cohorts: dose escalation occurred in 5 cohorts receiving 15 to 112 mg/d over 3 weeks (n=20), duration escalation in 3 cohorts receiving 112 mg/d over 4 to 6 weeks (n=12), and then 3 additional cohorts receiving 30 or 90 mg/d over 6 to 7 weeks (n=14). A maximum tolerated dose was not reached. One dose-limiting toxicity (grade 3 gastroenteritis and vomiting with hyponatremia) occurred in each of 2 separate cohorts at 112 mg. Nausea/vomiting and facial paresthesia during infusion seemed to be GC4419 dose-related. Severe OM occurred through 60 Gy in 4 of 14 patients (29%) dosed for 6 to 7 weeks, with median duration of only 2.5 days.
CONCLUSIONS: The safety of GC4419 concurrently with chemoradiation for OCC was acceptable. Toxicities included nausea/vomiting and paresthesia. Doses of 30 and 90 mg/d administered for 7 weeks were selected for further study. In an exploratory analysis, severe OM seemed less frequent and briefer than expected
Relationship Between Increased In Vivo Meniscal Loads and Abnormal Tibiofemoral Surface Alignment in ACL deficient Sheep is Varied
Developing young people's sense of self and place through sport
Previous research has recognized positive health implications, both physical and mental, as an outcome of participation in leisure pursuits. They provide opportunities for self-expression and stress reduction, as well as an environment in which people can socialize. Leisure activities, specifically sport activities, can play a significant role in young people's identity development. This paper explores the leisure activities in which young people in Adelaide, Australia participate. It examines the role of leisure activities in terms of young people's identity and feelings towards their hometown. This study consisted of semi-structured focus groups conducted with 24 senior high school students, followed by a survey resulting in 226 useable responses. Respondents were aged between 16 and 18 years of age. From the range of activities identified and explored, the results revealed sports activities to have the greatest impact on young people's lives. The results demonstrated that frequency of participation has a significant effect on young people's involvement levels and how they identify with the activity
An XMM-Newton view of the cluster of galaxies Abell 85
We have observed the cluster of galaxies Abell 85 with XMM-Newton. These data
have allowed us to confirm in a previous paper the existence of the extended 4
Mpc filament detected by the ROSAT PSPC in the neighbourhood of this cluster,
and to determine an X-ray temperature of about about 2 keV. We now present a
thorough analysis of the properties of the X-ray gas in the cluster itself,
including temperature and metallicity maps for the entire cluster. These
results show that Abell 85 had intense merging activity in the past and is not
fully relaxed, even in the central region. We have also determined the
individual abundances for some iron-group metals and alpha-elements in various
regions; the ratios of these metallicities to the iron abundance show that both
supernova types Ia and II must be involved in the intra-cluster gas enrichment.
Spectral analysis of the central region suggests a different redshift of the
X-ray emitting gas compared to the mean cluster velocity derived from galaxy
member redshifts. We discuss the implications of the difference between the cD
galaxy redshift, the mean galaxy redshift and the hot gas redshift, as well as
the possibility of several groups being accreted on to Abell 85. Finally, we
obtain the dynamical mass profile and baryon fraction taking into account the
new determined temperature profile. The dynamical mass in Abell 85 has a steep
density profile, similar to the ones found in N-body simulations.Comment: Accepted for publication in Astronomy & Astrophysic
Many-body Theory vs Simulations for the pseudogap in the Hubbard model
The opening of a critical-fluctuation induced pseudogap (or precursor
pseudogap) in the one-particle spectral weight of the half-filled
two-dimensional Hubbard model is discussed. This pseudogap, appearing in our
Monte Carlo simulations, may be obtained from many-body techniques that use
Green functions and vertex corrections that are at the same level of
approximation. Self-consistent theories of the Eliashberg type (such as the
Fluctuation Exchange Approximation) use renormalized Green functions and bare
vertices in a context where there is no Migdal theorem. They do not find the
pseudogap, in quantitative and qualitative disagreement with simulations,
suggesting these methods are inadequate for this problem. Differences between
precursor pseudogaps and strong-coupling pseudogaps are also discussed.Comment: Accepted, Phys. Rev. B15 15Mar00. Expanded version of original
submission, Latex, 8 pages, epsfig, 5 eps figures (Last one new). Discussion
on fluctuation and strong coupling induced pseudogaps expande
The Mixing and Transport Properties of the Intra Cluster Medium: a numerical study using tracers particles
We present a study of the mixing properties of the simulated intra cluster
Medium, using tracers particles that are advected by the gas flow during the
evolution of cosmic structures. Using a sample of seven galaxy clusters (with
masses in the range of M=2-3 10^14Msol/h) simulated with a peak resolution of
25kpc/h up to the distance of two virial radii from their centers, we
investigate the application of tracers to some important problems concerning
the mixing of the ICM. The transport properties of the evolving ICM are studied
through the analysis of pair dispersion statistics and mixing distributions. As
an application, we focus on the transport of metals in the ICM. We adopt simple
scenarios for the injection of metal tracers in the ICM, and find remarkable
differences of metallicity profiles in relaxed and merger systems, also through
the analysis of simulated emission from Doppler-shifted Fe XXIII lines.Comment: 19 pages, 24 figures, Astronomy and Astrophysics accepted; Final
version after language editing and updating the bibliograph
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