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We demonstrate how time integration of stochastic differential equations (i.e., Brownian dynamics simulations) can be combined with continuum numerical analysis techniques to analyze the dynamics of liquid crystalline polymers (LCPs). Sidestepping the necessity of obtaining explicit closures, the approach analyzes the (unavailable in closed form) "coarse" macroscopic equations, estimating the necessary quantities through appropriately initialized, short "bursts" of Brownian dynamics simulation. Through this approach, both stable and unstable branches of the equilibrium bifurcation diagram are obtained for the Doi model of LCPs and their "coarse stability" is estimated. Additional macroscopic computational tasks enabled through this approach, such as coarse projective integration and coarse stabilizing controller design, are also demonstrated. [ABSTRACT FROM AUTHOR]

Human-elephant conflict, in particular the damage caused by elephants to smallholder crops, is a major challenge to the conservation of African elephant Loxodonta africana. Conventional tools used to address this problem are capital intensive and require high levels of expertise. In recent years simple, affordable farm-based elephant deterrents, using locally available materials, have been encouraged by a number of human-elephant conflict researchers. There are very few published studies demonstrating the performance of these deterrents, however, and little is known about levels of uptake among smallholder farmers. We trialled a number of such farm-based elephant deterrents with local farmers in three sites within Laikipia District, Kenya. Levels of crop raiding declined after the introduction of treatments but not significantly when compared with control farms. Variable levels of uptake among the participating farmers made it difficult to draw clear conclusions from the trials. However, participating farmers were positive about the deterrent effect of the tools introduced, corroborated by their willingness to make financial commitments towards sustaining future trials. Availability of household labour, local politics, and insecurity were identified as important barriers to uptake of some of the deterrents introduced. Household labour availability should be a key consideration in future endeavours to trial farm-based elephant deterrents. [ABSTRACT FROM AUTHOR]

Preservation of the facial nerve during acoustic neuroma resection may be enhanced by the use of intraoperative electrical stimulation. Although stimulation of the extratemporal facial nerve is an effective and established procedure, anatomic differences of the intradural facial nerve and its microenvironment demand more exacting stimulus protocols. The absence of epineurium may make the intradural nerve more susceptible to mechanical or electrical trauma while intermittent pooling of cerebrospinal fluid (CSF) at the cerebellopontine angle may shunt current away from nerve. Four stimulus configurations were examined under varying conditions simulating CSF pooling. The results indicated that: 1. insulation of stimulating electrodes prevents CSF current shunting and allows utilization of a constant current source, and 2. monopolar and bipolar configurations demonstrate significantly different electrical characteristics which may be employed selectively based upon specific clinical goals. [ABSTRACT FROM AUTHOR]

The giant cholesterol cyst (GCC) of the petrous apex may now be considered a distinct clinical entity and should be considered in the differential diagnosis of lesions of the midcranial skull base. This benign cystic lesion of the petrous apex gradually enlarges and may produce progressive bone erosion and serial neurologic deficits of the cranial nerves within the temporal bone and jugular foramen. We report here five instances of this lesion (3 patients with unilateral and 1 patient with bilateral petrous apex lesions) and describe the natural history, diagnostic evaluation, pathology, and surgical management. [ABSTRACT FROM AUTHOR]

Persons with diminished or absent vestibulo-ocular reflexes (VORs) are thought to have difficulty with ocular stabilization during sufficiently rapid head movements. This suggests the hypothesis that labyrinthine defective individuals might have impaired visual abilities when in a moving motor vehicle. Ten licensed drivers likely to have abnormal VORs were recruited to assess this possibility. Their labyrinthine function was indexed by measurements of ocular counterroll responses to static head tilt and the nystagmus induced with caloric stimulations. Each person was evaluated on a visual task, i.e., answers to questions about alphanumeric information read from a stationary sign while sitting still and while riding in a car. Comparisons of vision scores tend to be lower in the moving than in the still condition. Furthermore, these decrements appear more closely related to the magnitudes of ocular counterroll than to the caloric reflexes. These results have implications concerning otolithic vs. semicircular canal function, vehicle operations by vestibular-impaired individuals, and evaluations of clinical treatments which employ vestibulotoxic drugs. [ABSTRACT FROM AUTHOR]

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Advances in neurotologic diagnosis and surgery has pointed to the need for a complete reassessment of the relationship and significance of the jugular bulb and sigmoid sinus is discussed and selected temporal bone sections presented to illustrate the varying locations of the jugualr bulb. Considerations in differential diagnosis are presented and examples of surgical procedures are discussed wherein the jugular bulb was encountered and the methods of management are detailed in these instances. [ABSTRACT FROM AUTHOR]