320 research outputs found
Sexual Harassment: An Analysis of North Dakota Personnel Policy
A telephone survey was used to measure North Dakota state employees\u27 experience with sexual harassment on the job. Survey respondents who reported being sexually harassed were asked an additional set of questions aimed at quantifying the experience, its effects and use of formal remedies. Expectations about survey results were generated from a review of the literature and other survey findings. While many expectations were not supported by the data, several important findings emerged. Specifically, 17.1 percent of all respondents, including 22.9 percent of women respondents and 10.7 percent of all male respondents reported being sexually harassed in state government during the past two years. This finding is significant at the .05 level. Results also show women in the state work force are more likely to be sexually harassed than men. However, a surprisingly large number of male respondents reported being harassed. Interestingly, none of the harassment victims used organizational remedies to deal with the harassment. Data generated by this survey was compared to prominant sexual harassment theories and the results of other scientific research, and a number of recommendations to improve or enhance the use of state policy are made
Why Care: Complex Evolutionary History of Human Healthcare Networks
One of the striking features of human social complexity is that we provide care to sick and contagious individuals, rather than avoiding them. Care-giving is a powerful strategy of disease control in human populations today; however, we are not the only species which provides care for the sick. Widespread reports occurring in distantly related species like cetaceans and insects suggest that the building blocks of care for the sick are older than the human lineage itself. This raises the question of what evolutionary processes drive the evolution of such care in animals, including humans. I synthesize data from the literature to evaluate the diversity of care-giving behaviors and conclude that across the animal kingdom there appear to be two distinct types of care-behaviors, both with separate evolutionary histories: (1) social care behaviors benefitting a sick individual by promoting healing and recovery and (2) community health behaviors that control pathogens in the environment and reduce transmission within the population. By synthesizing literature from psychology, anthropology, and biology, I develop a novel hypothesis (Hominin Pathogen Control Hypothesis) to explain how these two distinct sets of behaviors evolved independently then merged in the human lineage. The hypothesis suggests that social care evolved in association with offspring care systems whereas community health behaviors evolved as a type of niche construction. These two types of behaviors merged in humans to produce complex, multi-level healthcare networks in humans. Moreover, each type of care increases selection for the other, generating feedback loops that selected for increasing healthcare behaviors over time. Interestingly, domestication processes may have contributed to both social care and community health aspects of this process
Does the continuum theory of dynamic fracture work?
We investigate the validity of the Linear Elastic Fracture Mechanics approach
to dynamic fracture. We first test the predictions in a lattice simulation,
using a formula of Eshelby for the time-dependent Stress Intensity Factor.
Excellent agreement with the theory is found. We then use the same method to
analyze the experiment of Sharon and Fineberg. The data here is not consistent
with the theoretical expectation.Comment: 4 page
Nonlinear lattice model of viscoelastic Mode III fracture
We study the effect of general nonlinear force laws in viscoelastic lattice
models of fracture, focusing on the existence and stability of steady-state
Mode III cracks. We show that the hysteretic behavior at small driving is very
sensitive to the smoothness of the force law. At large driving, we find a Hopf
bifurcation to a straight crack whose velocity is periodic in time. The
frequency of the unstable bifurcating mode depends on the smoothness of the
potential, but is very close to an exact period-doubling instability. Slightly
above the onset of the instability, the system settles into a exactly
period-doubled state, presumably connected to the aforementioned bifurcation
structure. We explicitly solve for this new state and map out its
velocity-driving relation
Development and Psychometric Properties of the Emotional Intelligence Admission Essay Scale
The purpose was to describe the development and psychometric properties of the Emotional Intelligence Admission Essay scale. The authors developed an admission essay question and rating scale designed to provide information about applicants’ emotional intelligence (EI). Content validity, convergent validity, interrater reliability, and internal consistency were established. The scale was also examined to determine if it could discriminate between students with and without professional behavior problems in the academic and fieldwork settings. Content validity was found to be high by a panel of three experts in EI (content validity index = 1.0). Convergent validity with the Assessing Emotions Scale was moderate (r = .46, p \u3c .02). Interrater reliability between two trained faculty raters was high (ICC = .91, p \u3c .000). Internal consistency of the scale was high with a Cronbach’s alpha of .95. This version of the scale was not able to discriminate between students with and without professional behavior problems. The moderate to strong psychometric properties suggest that the EI Admission Essay Scale has the ability to provide information about applicants’ EI. The wording of the essay question must be modified to better instruct applicants to address interpersonal conflict
The walls have ears: the role of plant CrRLK1Ls in sensing and transducing extracellular signals
In plants, organ formation and cell elongation require the constant adjustment of the dynamic and adaptable cell wall in response to environmental cues as well as internal regulators, such as light, mechanical stresses, pathogen attacks, phytohormones, and other signaling molecules. The molecular mechanisms that perceive these cues and translate them into cellular responses to maintain integrity and remodelling of the carbohydrate-rich cell wall for the coordination of cell growth are still poorly understood. In the last 3 years, the function of six membrane-localized receptor-like kinases (RLKs) belonging to the CrRLK1L family has been linked to the control of cell elongation in vegetative and reproductive development. Moreover, the presence of putative carbohydrate-binding domains in the extracellular domains of these CrRLK1Ls makes this receptor family an excellent candidate for coordinating cell growth, cell-cell communication, and constant cell wall remodelling during the plant life cycl
Velocity Fluctuations in Dynamical Fracture: the Role of Microcracks
We address the velocity fluctuations of fastly moving cracks in stressed
materials. One possible mechanism for such fluctuations is the interaction of
the main crack with micro cracks (irrespective whether these are existing
material defects or they form during the crack evolution). We analyze carefully
the dynamics (in 2 space dimensions) of one macro and one micro crack, and
demonstrate that their interaction results in a {\em large} and {\em rapid}
velocity fluctuation, in qualitative correspondence with typical velocity
fluctuations observed in experiments. In developing the theory of the dynamical
interaction we invoke an approximation that affords a reduction in mathematical
complexity to a simple set of ordinary differential equations for the positions
of the cracks tips; we propose that this kind of approximation has a range of
usefulness that exceeds the present context.Comment: 7 pages, 7 figure
Arrested Cracks in Nonlinear Lattice Models of Brittle Fracture
We generalize lattice models of brittle fracture to arbitrary nonlinear force
laws and study the existence of arrested semi-infinite cracks. Unlike what is
seen in the discontinuous case studied to date, the range in driving
displacement for which these arrested cracks exist is very small. Also, our
results indicate that small changes in the vicinity of the crack tip can have
an extremely large effect on arrested cracks. Finally, we briefly discuss the
possible relevance of our findings to recent experiments.Comment: submitted to PRE, Rapid Communication
Paternal kin recognition in the high frequency / ultrasonic range in a solitary foraging mammal
Background Kin selection is a driving force in the evolution of mammalian social complexity. Recognition of paternal kin using vocalizations occurs in taxa with cohesive, complex social groups. This is the first investigation of paternal kin recognition via vocalizations in a small-brained, solitary foraging mammal, the grey mouse lemur (Microcebus murinus), a frequent model for ancestral primates. We analyzed the high frequency/ultrasonic male advertisement (courtship) call and alarm call. Results Multi-parametric analyses of the calls’ acoustic parameters and discriminant function analyses showed that advertisement calls, but not alarm calls, contain patrilineal signatures. Playback experiments controlling for familiarity showed that females paid more attention to advertisement calls from unrelated males than from their fathers. Reactions to alarm calls from unrelated males and fathers did not differ. Conclusions 1) Findings provide the first evidence of paternal kin recognition via vocalizations in a small-brained, solitarily foraging mammal. 2) High predation, small body size, and dispersed social systems may select for acoustic paternal kin recognition in the high frequency/ultrasonic ranges, thus limiting risks of inbreeding and eavesdropping by predators or conspecific competitors. 3) Paternal kin recognition via vocalizations in mammals is not dependent upon a large brain and high social complexity, but may already have been an integral part of the dispersed social networks from which more complex, kin-based sociality emerged
Steady-State Cracks in Viscoelastic Lattice Models II
We present the analytic solution of the Mode III steady-state crack in a
square lattice with piecewise linear springs and Kelvin viscosity. We show how
the results simplify in the limit of large width. We relate our results to a
model where the continuum limit is taken only along the crack direction. We
present results for small velocity, and for large viscosity, and discuss the
structure of the critical bifurcation for small velocity. We compute the size
of the process zone wherein standard continuum elasticity theory breaks down.Comment: 17 pages, 3 figure
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