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Optical Delusions: Questioning and Shifting the Cyclical Nature of Human Choice, Time, and the Behaviors of the Greater Universe
Optical Delusions is an eighteen-minute dance performance piece that inquires, and quite literally smashes delusions that have become deeply rooted in the human understanding of personal choice and the concept of time. Inspired by the writings and teachings of physicist Brian Greene and the theories of philosopher and composer Friedrich Nietzsche, melded with my own experiences in harnessing the power of choice, the audience finds themselves questioning the nature of the circles that inherently exist in our universe. The nature of the circles comes to life as the piece utilizes a loop pedal machine following a live-feed, projected feedback loop that brings the space to life. Using mirrors as a metaphor for perception and beyond, the dancers interact with pieces of glass strewn across the space. They are also seen obliterating their own reflections in projected video images. Throughout my process I ask the critical question, how can we initiate change in the perpetual circles that inherently dominate our lives
Pressure-induced cell wall instability and growth oscillations in pollen tubes
In the seed plants, the pollen tube is a cellular extension that serves as a conduit through which male gametes are transported to complete fertilization of the egg cell. It consists of a single elongated cell which exhibits characteristic oscillations in growth rate until it finally bursts, completing its function. The mechanism behind the periodic character of the growth has not been fully understood. In this paper we show that the mechanism of pressure - induced symmetry frustration occurring in the wall at the transition-perimeter between the cylindrical and approximately hemispherical parts of the growing pollen tube, together with the addition of cell wall material, is sufficient to release and sustain mechanical self-oscillations and cell extension. At the transition zone, where symmetry frustration occurs and one cannot distinguish either of the involved symmetries, a kind of 'superposition state' appears where either single or both symmetry(ies) can be realized by the system. We anticipate that testifiable predictions made by the model (f ∝ √P) may deliver, after calibration, a new tool to estimate turgor pressure P from oscillation frequency f of the periodically growing cell. Since the mechanical principles apply to all turgor regulated walled cells including those of plant, fungal and bacterial origin, the relevance of this work is not limited to the case of the pollen tube
Observations on sexual dimorphism and social structure in the lizard Angolosaurus skoogi (Cordylidae) of the northern Namib Desert dunes
Angolosaurus skoogi is a large, herbivorous lizard of the northern Namib dune sea. Adults are sexually dimorphic in body size and colouration and these differences may be related to social organization. Whether the observed dimorphism is a result of the mating system, as is the case with several other herbivorous lizards, is unresolved. A scale character is described that provides an external indication of sex in non-reproductive individuals and thus provides a means of investigating questions pertaining to sexual dimorphism and other population level questions
Resiliency and Well-being as Moderators of Stress
College students experience a great deal of stress as they prepare for the transition from adolescence to adulthood. Furthermore, the ability to navigate stress and anxiety is challenged due to underdeveloped resiliency skills. Resiliency and well-being can act as a coping technique in building hope, commitment, accountability, and passion. The measurement of these factors can be an indication of how a person responds to stressful events or feelings. The study expected to see an interaction of resiliency as an overall moderator in the perception of stress based on actual stress level. The High Capacity Model of Resiliency Scale (H-CAP) was used for that specific testing of the components of resiliency. Stress was accounted for using the Undergraduate Stress Questionnaire (USQ), designed specifically for college students and typical stressful situations that they experience. Perceived stress was calculated using the Perceived Stress Scale (PSS). There was a positive correlation between actual stress and perceived stress as well as a significant difference in the stress level of the sample in comparison to the norms of the measures. Each component of resiliency reported a significant main effect with the stress scores, however; only commitment reported a significant interaction. This study has implications regarding the need for stress coping in college aged students
A renaissance in voice analysers as tools for detection of deception?
"The current situation in the world, and especially the threat of terrorism,
creates a demand for new technologies that allow observation of human
psychophysiological reactions without entering into direct contact with the
person and without that person’s knowledge, to evaluate the person’s honesty
(deception), intentions, hidden information, and information provided.
This has resulted in a revival of interest in devices and techniques for
investigating emotional changes in the sound of the human voice (Widacki
2007)."(...
Simple method to estimate cell wall extensibility coefficient by using only two cardinal numbers
In this short communication we consider the extensibility properties of the cell wall. This is accomplished by
a heuristically motivated equation for the expanding volume of the cell. The experimentally determined characteristic
time t0 and temperature T0 are the only numbers required for evaluating the effective yielding coefficient
F(t, T) in the respective time and temperature domains
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