1,269 research outputs found
The Influence of Biology and Commitment Beliefs on Jealousy Responses
Research on biological sex differences in romantic jealousy suggests that males are more upset by sexual infidelity and females are more upset by emotional infidelity. Researchers identify two types of jealousy (i.e., sexual and emotional) and two types of commitment (i.e., sexual exclusivity and relational duration). The type of jealousy experienced may be a rational or emotional response to different commitment beliefs rather than dependent on biological sex. A sample of 230 college students completed various measures of commitment and jealousy as part of an online survey. People who valued sexually exclusive relationships were more distressed by sexual infidelity. People who valued long-term relationships were more distressed by emotional infidelity. Commitment beliefs predict jealousy responses irrespective of biological sex
Process development of two high strength tantalum base alloys (ASTAR-1211C and ASTAR-1511C)
Two tantalum base alloys, Ta-12W-1.0Re-0.7Hf-0.025C(ASTAR-1211C) and Ta-15W-1.0Re-0.7Hf-0.025C(ASTAR-1511C), were cast as 12.5 cm (5 inch) diameter ingots and processed to swaged rod, sheet, forged plate, and tubing. Swaged rod was evaluated with respect to low temperature ductility, elevated temperature tensile properties, and elevated temperature creep behavior. A standard swaging process and final annealing schedule were determined. Elevated temperature tensile properties, low temperature impact properties, low temperature DBTT behavior, and extended elevated temperature creep properties were determined. A process for producing ASTAR-1211C and ASTAR-1511C sheet were developed. The DBTT properties of GTA and EB weld sheet given post-weld anneal and thermal aging treatments were determined using bend and tensile specimens. High and low temperature mechanical properties of forging ASTAR-1211C and ASTAR-1511C plate were determined as well as elevated temperature creep properties. Attempts to produce ASTAR-1211C tubing were partially successful while attempts to make ASTAR-1511C tubing were completely unsuccessful
Profilin reduces aggregation and phase separation of huntingtin N-terminal fragments by preferentially binding to soluble monomers and oligomers
Development of advanced high strength tantalum base alloys. Part 2: Scale-up investigation
Three experimental tantalum alloy compositions containing 14-16% W, 1% Re, 0.7% Hf, 0.025% C or 0.015% C and 0.015% N were prepared as two inch diameter ingots by consumable electrode vacuum arc melting. The as-cast ingots were processed by extrusion and swaging to one inch and 0.4 inch diameter rod and evaluated. Excellent high temperature forging behavior was exhibited by all three compositions. Creep strength at 2000 F to 2400 F was enhanced by higher tungsten additions as well as substitution of nitrogen for carbon. Weldability of all three compositions was determined to be adequate. Room temperature ductility was retained in the advanced tantalum alloy compositions as well as a notched/unnotched strength ratio of 1.4 for a notched bar having a K sub t = 2.9
Movement ecology and sex are linked to barn owl microbial community composition.
The behavioural ecology of host species is likely to affect their microbial communities, because host sex, diet, physiology, and movement behaviour could all potentially influence their microbiota. We studied a wild population of barn owls (Tyto alba) and collected data on their microbiota, movement, diet, size, coloration, and reproduction. The composition of bacterial species differed by the sex of the host and female owls had more diverse bacterial communities than their male counterparts. The abundance of two families of bacteria, Actinomycetaceae and Lactobacillaceae, also varied between the sexes, potentially as a result of sex differences in hormones and immunological function, as has previously been found with Lactobacillaceae in the microbiota of mice. Male and female owls did not differ in the prey they brought to the nest, which suggests that dietary differences are unlikely to underlie the differences in their microbiota. The movement behaviour of the owls was associated with the host microbiota in both males and females because owls that moved further from their nest each day had more diverse bacterial communities than owls that stayed closer to their nests. This novel result suggests that the movement ecology of hosts can impact their microbiota, potentially on the basis of their differential encounters with new bacterial species as the hosts move and forage across the landscape. Overall, we found that many aspects of the microbial community are correlated with the behavioural ecology of the host and that data on the microbiota can aid in generating new hypotheses about host behaviour
Roar of the Crowd: Noise-Related Safety Concerns in Sport
In sport the safety of staff, participants and spectators is of the utmost importance. Therefore, sport venue and event managers should take every precaution to address safety concerns while planning for and executing events or activities. While venue managers have a legal duty to protect fans and participants, federal regulations exist to ensure a safe workplace for all employees, including those at a sports event. This is a conceptual article intended to assist practitioners to identify potentially unexpected hazards within the work environment, as well as strategies to eliminate or manage them. The authors examine existing federal regulations, current research associated with hearing/noise-related concerns and specific research undertaken in the sport environment. The article concludes with recommended prevention strategies for facility and event managers to assist them in meeting their professional and legal obligations
Killer Jobs: The Dark Side of Being a Physical Education Teacher
The profession of physical education (PE) teacher involves a variety of risks. Most PE teachers or future teachers are aware of the risks associated with their students becoming injured. Sport law classes often discuss negligence, risk management, proper supervision, suitable equipment, appropriate instruction, proper matching of opponents, etc. The focus is primarily or exclusively on student safety. Rarely is the focus on the risks PE teachers face themselves. This article discusses the largely neglected topics of transportation, workplace violence, and slip/trip and falls, all of which are occupational hazards for PE teachers, potentially associated with serious injuries or death
Non-Equilibrium Field Dynamics of an Honest Holographic Superconductor
Most holographic models of superconducting systems neglect the effects of
dynamical boundary gauge fields during the process of spontaneous
symmetry-breaking. Usually a global symmetry gets broken. This yields a
superfluid, which then is gauged "weakly" afterwards. In this work we build
(and probe the dynamics of) a holographic model in which a local boundary
symmetry is spontaneously broken instead. We compute two-point functions of
dynamical non-Abelian gauge fields in the normal and in the broken phase, and
find non-trivial gapless modes. Our AdS3 gravity dual realizes a p-wave
superconductor in (1+1) dimensions. The ground state of this model also breaks
(1+1)-dimensional parity spontaneously, while the Hamiltonian is
parity-invariant. We discuss possible implications of our results for a wider
class of holographic liquids.Comment: 32 pages, 12 figures; v3: string theory derivation of setup added
(section 3.1), improved presentation, version accepted by JHEP; v2: paragraph
added to discussion, figure added, references added, typos correcte
Molecular Phylogenetics and the Diversification of Hummingbirds
SummaryThe tempo of species diversification in large clades can reveal fundamental evolutionary mechanisms that operate on large temporal and spatial scales [1–4]. Hummingbirds have radiated into a diverse assemblage of specialized nectarivores comprising 338 species, but their evolutionary history has not, until now, been comprehensively explored. We studied hummingbird diversification by estimating a time-calibrated phylogeny for 284 hummingbird species, demonstrating that hummingbirds invaded South America by ∼22 million years ago, and subsequently diversified into nine principal clades (see [5–7]). Using ancestral state reconstruction and diversification analyses, we (1) estimate the age of the crown-group hummingbird assemblage, (2) investigate the timing and patterns of lineage accumulation for hummingbirds overall and regionally, and (3) evaluate the role of Andean uplift in hummingbird speciation. Detailed analyses reveal disparate clade-specific processes that allowed for ongoing species diversification. One factor was significant variation among clades in diversification rates. For example, the nine principal clades of hummingbirds exhibit ∼15-fold variation in net diversification rates, with evidence for accelerated speciation of a clade that includes the Bee, Emerald, and Mountain Gem groups of hummingbirds. A second factor was colonization of key geographic regions, which opened up new ecological niches. For example, some clades diversified in the context of the uplift of the Andes Mountains, whereas others were affected by the formation of the Panamanian land bridge. Finally, although species accumulation is slowing in all groups of hummingbirds, several major clades maintain rapid rates of diversification on par with classical examples of rapid adaptive radiation
Zero-variance principle for Monte Carlo algorithms
We present a general approach to greatly increase at little cost the
efficiency of Monte Carlo algorithms. To each observable to be computed we
associate a renormalized observable (improved estimator) having the same
average but a different variance. By writing down the zero-variance condition a
fundamental equation determining the optimal choice for the renormalized
observable is derived (zero-variance principle for each observable separately).
We show, with several examples including classical and quantum Monte Carlo
calculations, that the method can be very powerful.Comment: 9 pages, Latex, to appear in Phys. Rev. Let
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