22,557 research outputs found
The influence of lifelong learning on mood
Mood state was assessed both before and after four different two-hour classes in the Osher Lifelong Learning Institute at Santa Clara University with the self-report Profile of Mood States-Brief Form (POMS-BF) developed by McNair, Lorr, and Droppleman (1992). Sixty-eight students (60% women), ages 49 to 92, filled in the 5-point mood assessment survey rating how they felt at that moment prior to the start of class and again two hours later, at the end of class. At the start of class these students reported very low levels of negative affect (tension, anger, depression, confusion, fatigue). Following the two-hour Osher class students felt even less angry, less tense, and less depressed than they were before the class. These results are discussed in relation to mood regulation and the detrimental impact of negative affect on cognition (e.g., Wilson, Mendes de Leon, Bennett, Bienias, Evans, 2004)
Drivers of Microbial Risk for Direct Potable Reuse and de Facto Reuse Treatment Schemes: The Impacts of Source Water Quality and Blending.
Although reclaimed water for potable applications has many potential benefits, it poses concerns for chemical and microbial risks to consumers. We present a quantitative microbial risk assessment (QMRA) Monte Carlo framework to compare a de facto water reuse scenario (treated wastewater-impacted surface water) with four hypothetical Direct Potable Reuse (DPR) scenarios for Norovirus, Cryptosporidium, and Salmonella. Consumer microbial risks of surface source water quality (impacted by 0-100% treated wastewater effluent) were assessed. Additionally, we assessed risks for different blending ratios (0-100% surface water blended into advanced-treated DPR water) when source surface water consisted of 50% wastewater effluent. De facto reuse risks exceeded the yearly 10-4 infections risk benchmark while all modeled DPR risks were significantly lower. Contamination with 1% or more wastewater effluent in the source water, and blending 1% or more wastewater-impacted surface water into the advanced-treated DPR water drove the risk closer to the 10-4 benchmark. We demonstrate that de facto reuse by itself, or as an input into DPR, drives microbial risks more so than the advanced-treated DPR water. When applied using location-specific inputs, this framework can contribute to project design and public awareness campaigns to build legitimacy for DPR
Fluid moment hierarchy equations derived from gauge invariant quantum kinetic theory
The gauge invariant electromagnetic Wigner equation is taken as the basis for
a fluid-like system describing quantum plasmas, derived from the moments of the
gauge invariant Wigner function. The use of the standard, gauge dependent
Wigner function is shown to produce inconsistencies, if a direct correspondence
principle is applied. The propagation of linear transverse waves is considered
and shown to be in agreement with the kinetic theory in the long wavelength
approximation, provided an adequate closure is chosen for the macroscopic
equations. A general recipe to solve the closure problem is suggested.Comment: 12 pages, 1 figur
On the Integrability and Chaos of an N=2 Maxwell-Chern-Simons-Higgs Mechanical Model
We apply different integrability analysis procedures to a reduced (spatially
homogeneous) mechanical system derived from an off-shell non-minimally coupled
N=2 Maxwell-Chern-Simons-Higgs model that presents BPS topological vortex
excitations, numerically obtained with an ansatz adopted in a special -
critical coupling - parametric regime. As a counterpart of the regularity
associated to the static soliton-like solution, we investigate the possibility
of chaotic dynamics in the evolution of the spatially homogeneous reduced
system, descendant from the full N=2 model under consideration. The originally
rich content of symmetries and interactions, N=2 susy and non-minimal coupling,
singles out the proposed model as an interesting framework for the
investigation of the role played by (super-)symmetries and parametric domains
in the triggering/control of chaotic behavior in gauge systems.
After writing down effective Lagrangian and Hamiltonian functions, and
establishing the corresponding canonical Hamilton equations, we apply global
integrability Noether point symmetries and Painleveproperty criteria to both
the general and the critical coupling regimes. As a non-integrable character is
detected by the pair of analytical criteria applied, we perform suitable
numerical simulations, as we seek for chaotic patterns in the system evolution.
Finally, we present some Comments on the results and perspectives for further
investigations and forthcoming communications.Comment: 18 pages, 5 figure
Magnon Mediated Electric Current Drag Across a Ferromagnetic Insulator Layer
In a semiconductor hererostructure, the Coulomb interaction is responsible
for the electric current drag between two 2D electron gases across an electron
impenetrable insulator. For two metallic layers separated by a ferromagnetic
insulator (FI) layer, the electric current drag can be mediated by a
nonequilibrium magnon current of the FI. We determine the drag current by using
the semiclassical Boltzmann approach with proper boundary conditions of
electrons and magnons at the metal-FI interface.Comment: 13 pages, 2 figures: to appear in PR
Trust in the US-EU fruit and vegetable chain: Do US exporters understand EU importers?
Research on organizational and inter organizational trust has become an important field in management and marketing literature, as it is perceived as a pivotal aspect of business transactions. However, clarifications are still needed on the issue of whom we trust; is the person whom we are trading with trusted, or the organization, or just the product‐quality? Not only has this question not been answered within this field of research, neither have cultural differences have been described to any great extent. Additionally, if the perceived factors important to establish trusting relationships may or may not be the same on the buyers and the sellers side in international business transaction in food chains. The primary objective of this research study therefore is to identify how well US exporters understand the elements of trust that establish strong relationships with EU importers. The Analytical Hierarchy Process was used to evaluate the importance of different trust elements in interviews conducted with US exporters and EU importers of fruits and vegetables. Results are compared, providing both a picture of the important facets of trust, as well as whether the partners understand the perspectives of the other partner
Cognition and leisure time activities of older adults
Older adults have much more leisure time today than they have had in the past. Evidence points to the connection between engagement in physical exercise, a leisure time activity, and the overall health of older adults. Because health is an important issue, especially as we age, it is helpful to know that we have some control over it as we age. Cognition, i.e., our ability to remember, to pay attention, and to think, is also a concern in aging. Is it possible that the choices we make about leisure time activities may influence our cognitive abilities in old age? This critical review of the literature examines the effect of three leisure time activities - socializing, physical exercise, and mental exercise - on cognition in older adults
- …