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Tackling the "Galacticos" effect: team familiarity and the performance of star-studded projects
Findings on the performance implications of assembling star-studded teams have remained rather mixed. We elaborate on the theoretical reasons for current inconclusive findings and delineate more precise boundary conditions for studying the relationship between stars and project-level performance. Specifically, we argue that lack of scholarly attention to team familiarity may account for empirical resultsâ observed inconsistency. Our findings show that a history of past collaboration reduces the downsides of having too many stars within the same team. Previous interactions enhance coordination efforts by reducing conflicts among team members. We situate the analysis within the context of the Hollywood film industry over the period 1992â2004. The theoretical implications of the results are discussed
Students as co-creators of teaching approaches, course design and curricula: implications for academic developers
Within higher education, studentsâ voices are frequently overlooked in the design of teaching approaches, courses and curricula. In this paper we outline the theoretical background to arguments for including students as partners in pedagogical planning processes. We present examples where students have worked collaboratively in design processes along with the beneficial outcomes of these examples. Finally we focus on some of the implications and opportunities for academic developers of proposing collaborative approaches to pedagogical planning
Low-Lying Excited States and Low-Temperature Properties of an Alternating Spin-1 / Spin-1/2 Chain : A DMRG study
We report spin wave and DMRG studies of the ground and low-lying excited
states of uniform and dimerized alternating spin chains. The DMRG procedure is
also employed to obtain low-temperature thermodynamic properties of the system.
The ground state of a 2N spin system with spin-1 and spin-1/2 alternating from
site to site and interacting via an antiferromagnetic exchange is found to be
ferrimagnetic with total spin from both DMRG and spin wave analysis.
Both the studies also show that there is a gapless excitation to a state with
spin and a gapped excitation to a state with spin .
Surprisingly, the correlation length in the ground state is found to be very
small from both the studies for this gapless system. For this very reason, we
show that the ground state can be described by a variational ``ansatz'' of the
product type. DMRG analysis shows that the chain is susceptible to a
conditional spin-Peierls' instability. The DMRG studies of magnetization,
magnetic susceptibility () and specific heat show strong magnetic-field
dependence. The product shows a minimum as a function of
temperature() at low-magnetic fields and the minimum vanishes at
high-magnetic fields. This low-field behaviour is in agreement with earlier
experimental observations. The specific heat shows a maximum as a function of
temperature and the height of the maximum increases sharply at high magnetic
fields. It is hoped that these studies will motivate experimental studies at
high-magnetic fields.Comment: 22 pages in latex; 16 eps figures available upon reques
Dynamical Structure Factor for the Alternating Heisenberg Chain: A Linked Cluster Calculation
We develop a linked cluster method to calculate the spectral weights of
many-particle excitations at zero temperature. The dynamical structure factor
is expressed as a sum of exclusive structure factors, each representing
contributions from a given set of excited states. A linked cluster technique to
obtain high order series expansions for these quantities is discussed. We apply
these methods to the alternating Heisenberg chain around the dimerized limit
(), where complete wavevector and frequency dependent spectral
weights for one and two-particle excitations (continuum and bound-states) are
obtained. For small to moderate values of the inter-dimer coupling parameter
, these lead to extremely accurate calculations of the dynamical
structure factors. We also examine the variation of the relative spectral
weights of one and two-particle states with bond alternation all the way up to
the limit of the uniform chain (). In agreement with Schmidt and
Uhrig, we find that the spectral weight is dominated by 2-triplet states even
at , which implies that a description in terms of triplet-pair
excitations remains a good quantitative description of the system even for the
uniform chain.Comment: 26 pages, 17 figure
Interplay Between Time-Temperature-Transformation and the Liquid-Liquid Phase Transition in Water
We study the TIP5P water model proposed by Mahoney and Jorgensen, which is
closer to real water than previously-proposed classical pairwise additive
potentials. We simulate the model in a wide range of deeply supercooled states
and find (i) the existence of a non-monotonic ``nose-shaped'' temperature of
maximum density line and a non-reentrant spinodal, (ii) the presence of a low
temperature phase transition, (iii) the free evolution of bulk water to ice,
and (iv) the time-temperature-transformation curves at different densities.Comment: RevTeX4, 4 pages, 4 eps figure
The effects of a controlled worksite environmental intervention on determinants of dietary behavior and self-reported fruit, vegetable and fat intake
BACKGROUND: Eating patterns in Western industrialized countries are characterized by a high energy intake and an overconsumption of (saturated) fat, cholesterol, sugar and salt. Many chronic diseases are associated with unhealthy eating patterns. On the other hand, a healthy diet (low saturated fat intake and high fruit and vegetable intake) has been found important in the prevention of health problems, such as cancer and cardio-vascular disease (CVD). The worksite seems an ideal intervention setting to influence dietary behavior. The purpose of this study is to present the effects of a worksite environmental intervention on fruit, vegetable and fat intake and determinants of behavior. METHODS: A controlled trial that included two different governmental companies (n = 515): one intervention and one control company. Outcome measurements (short-fat list and fruit and vegetable questionnaire) took place at baseline and 3 and 12 months after baseline. The relatively modest environmental intervention consisted of product information to facilitate healthier food choices (i.e., the caloric (kcal) value of foods in groups of products was translated into the number of minutes to perform a certain (occupational) activity to burn these calories). RESULTS: Significant changes in psychosocial determinants of dietary behavior were found; subjects at the intervention worksite perceived more social support from their colleagues in eating less fat. But also counter intuitive effects were found: at 12 months the attitude and self-efficacy towards eating less fat became less positive in the intervention group. No effects were found on self-reported fat, fruit and vegetable intake. CONCLUSION: This environmental intervention was modestly effective in changing behavioral determinant towards eating less fat (social support, self-efficacy and attitude), but ineffective in positively changing actual fat, fruit and vegetable intake of office workers
Ab initio van der Waals interactions in simulations of water alter structure from mainly tetrahedral to high-density-like
The structure of liquid water at ambient conditions is studied in ab initio
molecular dynamics simulations using van der Waals (vdW) density-functional
theory, i.e. using the new exchange-correlation functionals optPBE-vdW and
vdW-DF2. Inclusion of the more isotropic vdW interactions counteracts highly
directional hydrogen-bonds, which are enhanced by standard functionals. This
brings about a softening of the microscopic structure of water, as seen from
the broadening of angular distribution functions and, in particular, from the
much lower and broader first peak in the oxygen-oxygen pair-correlation
function (PCF), indicating loss of structure in the outer solvation shells. In
combination with softer non-local correlation terms, as in the new
parameterization of vdW-DF, inclusion of vdW interactions is shown to shift the
balance of resulting structures from open tetrahedral to more close-packed. The
resulting O-O PCF shows some resemblance with experiment for high-density water
(A. K. Soper and M. A. Ricci, Phys. Rev. Lett., 84:2881, 2000), but not
directly with experiment for ambient water. However, an O-O PCF consisting of a
linear combination of 70% from vdW-DF2 and 30% from experiment on low-density
liquid water reproduces near-quantitatively the experimental O-O PCF for
ambient water, indicating consistency with a two-liquid model with fluctuations
between high- and low-density regions
Critical animal and media studies: Expanding the understanding of oppression in communication research
Critical and communication studies have traditionally neglected the oppression conducted by humans towards other animals. However, our (mis)treatment of other animals is the result of public consent supported by a morally speciesist-anthropocentric system of values. Speciesism or anthroparchy, as much as any other mainstream ideologies, feeds the media and at the same time is perpetuated by them. The goal of this article is to remedy this neglect by introducing the subdiscipline of Critical Animal and Media Studies. Critical Animal and Media Studies takes inspiration both from critical animal studies â which is so far the most consolidated critical field of research in the social sciences addressing our exploitation of other animals â and from the normative-moral stance rooted in the cornerstones of traditional critical media studies. The authors argue that the Critical Animal and Media Studies approach is an unavoidable step forward for critical media and communication studies to engage with the expanded circle of concerns of contemporary ethical thinking
LOGISTICS IN CONTESTED ENVIRONMENTS
This report examines the transport and delivery of logistics in contested environments within the context of great-power competition (GPC). Across the Department of Defense (DOD), it is believed that GPC will strain our current supply lines beyond their capacity to maintain required warfighting capability. Current DOD efforts are underway to determine an appropriate range of platforms, platform quantities, and delivery tactics to meet the projected logistics demand in future conflicts. This report explores the effectiveness of various platforms and delivery methods through analysis in developed survivability, circulation, and network optimization models. Among other factors, platforms are discriminated by their radar cross-section (RCS), noise level, speed, cargo capacity, and self-defense capability. To maximize supply delivered and minimize the cost of losses, the results of this analysis indicate preference for utilization of well-defended convoys on supply routes where bulk supply is appropriate and smaller, and widely dispersed assets on shorter, more contested routes with less demand. Sensitivity analysis on these results indicates system survivability can be improved by applying RCS and noise-reduction measures to logistics assets.Director, Warfare Integration (OPNAV N9I)Major, Israel Defence ForcesCivilian, Singapore Technologies Engineering Ltd, SingaporeCommander, Republic of Singapore NavyCommander, United States NavyCaptain, Singapore ArmyLieutenant, United States NavyLieutenant, United States NavyMajor, Republic of Singapore Air ForceCaptain, United States Marine CorpsLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyCaptain, Singapore ArmyLieutenant Junior Grade, United States NavyCaptain, Singapore ArmyLieutenant Colonel, Republic of Singapore Air ForceApproved for public release. distribution is unlimite
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